\0Z ijJ (g. ias;*:^ BOUGHT WITH THE INCOME I FROM THE SAGE ENDOWNENT FUND THE GIFT OP 1891 ENGINEERING LiBRAR^ AJ^.^y^i v/wm. Cornell University Library QE 265.A5 1895 Guide to the coliections of rocks and fo 3 1924 004 017 905 The original of tiiis book is in tine Cornell University Library. There are no known copyright restrictions in the United States on the use of the text. http://www.archive.org/details/cu31924004017905 GUIDE COLLECTIONS OF HOCKS AND FOSSILS BELONGISre TO THB GEOLOGICAL SUKVEY OF IRELAND, AERANGED IN ROOM m. E. OF THE MUSEUM OF SCIENCE AND AST, DUBLIN. A. M'HENRY, m.r.i.a., and W. W. WAl'TS, m.a., f.g.S. DUBLIN: PRINTED FOR HER MAJESTY'S STATIONERY OFFICE, BY ALEXANDER 3.^H0M & 00. (Limited). And to be purchased, either directly or thiough any Boolcaeller, from IIODUISS, FIGGIS & Co. (Limited), 104, Ghafton-street, Dublin ; or EYKIL & SPOTTISWOODK, Kast Hahding-stbeet, Fleet-stbeet, E.C. ; or ■JUllN MlilNZIES & Co., 12, Hakoveb-stkeet, Edisburub, aud 90, West Nile-street, Glashow. 1895. Price Ninepenoe. GUIDE COLLECTIONS OF EOCES AND FOSSILS BELONGING TO THE GEOLOGICAL SURVEY OF IRELAND, AEEANGED IN ROOM in. E. OF THE MUSEUM OF SCIENCE AND ART, DUBLIN. BY A. M'HENRY, m.r.i.a., and W. W. WA'i'TS, m.a., f.g.s. DUBLIN: PRINTED FOR HER MAJESTY'S STATIONERY OFFICE, BY ALEXANDER THOM & CO. (Limited). And to be purchased, either directly or thiough any Bookseller, from HODGES, FIGGIS & Co. (Limited), 104, Gkaftos-strebt, Dublin ; or JiYKB & SPOTTISWOODK, East Harding-street, Fleet-street, E.C. ; or JOH^ MENZIES & Co., 12, Hakovek-street, EDiNBUROii, and 90, We8t Nile-street, Glasgow, 1895. Price Nmepence, I- o o (^ i,. UJ -J Q -J k 15: u. E ■»: a; is 5 ^ ^ h ^ <5 -^ '?* "^ ^ --S^ ^ ^ is ^ '^ -^ S 5^ ss ^s^ § ^ ntain order s ^ 8^ -S i -**;,, ^ 1 1 DID I 0; NOTICE This Guide is issued as one of the series of handbooks to Collections deposited in the Science and Art Museum, Dublin. It may be said to supply a real want, and therefore, although the possibility of the collection being removed to a new gallery, at no very distant period, is not out of sight, the necessity for early publication is nevertheless manifest. V. BALL, Director, Science and Art Museum, Dublin. 30th November, 1894. a2 PREFACE, The nucleus of the Collection to ■which this volume is a Guide, was formed under the supervision of Professor J. Beete Jukes, as Director of the Geological Survey of Ireland. The specimens were fully described by him in an elaborate catalogue, which has long been out of print, and is now difficult to procure. After his time the collection was considerably increased under the direction of his successor. Professor E. Hull, and within the last few years it has been still further enlarged. Advantage has been taken of its removal to the present Museum of Science and Art to re-arrange it entirely, and illustrate it by means of descriptive labels, diagrams, pho- tographs, drawings and maps. The general scheme of arrangement, combining reference to the great political divi- sions of the country, together with the petrographical and stratigraphical relations of the specimens, was planned by myself, and has been carried out with much care and success by Messrs. M'Heniy and Watts. In order to make the collec- tion still further useful, both to students and the general public, it has been thought desirable to prepare a General Guide which, without being a mere catalogue repeating the descriptions on the labels affixed to the specimens, will form a convenient handbook, not only to the contents of the gallery, but to the general geology of Ireland. Great care has been taken to preserve what was of per- manent value in the original collection, and to fit it into the present arrangement, while at the same time all that is still of importance in Jukes' Catalogue has been incorporated in the labels of the specimens and in the present volume. 6 PREFACE. Besides a large series of rock-specimens, there is also an important collection of Irish fossils arranged in strati- graphical order. These specimens, as well as the rocks, have been almost entii-ely collected by the Geological Survey, and are still continually receiving additions. They were originally named by J- W. Salter and W. H. Baily. They comprise also a portion of the famous Port- lock Collection, the rest of which, including the type- specimens, is preserved in the Museum of Practical Geology in London. In the preparation of this Handbook, Mr. M^Hem-y's great local knowledge of Ireland and of Irish geology has been of use on every page. Having chief charge of the fossil collec- tions, he has superintended the labelling, naming, and re- tableting of the specimens, and has furnished the list of organic remains which were used in drawing up the Palseon- tological part of this volume, A large number of the rock- specimens in the old series having been collected by him, he has been able to furnish important information regarding them, and the geology of the districts from which they were obtained. The actual writing of the Handbook has been assigned to Mr. Watts. In addition to the copious materials supplied to him by Mr. M'Henry, he has himself furnished many original details regarding the Petrography. He has been under the necessity of carefully analysing the previous literature of Irish geology. Every possible source of infor- mation open to him has been made use of, but in a book of this description it is neither possible nor desirable to load the pages with references to authors. It must suffice to make here a general acknowledgment of indebtedness. No fresh work on Irish geology can appear without an expression of special gratitude to three great observers — Griffith, Portlock, and Jukes— whose labour.s as admirable pioneers and leaders so largely aided the advance of geo- logical science in their time. PREFACE. 7 Tlie most constant and valuable sources of information in the preparation of the following pages have been the maps, memoii-s, and other publications of the Geological Survey, including the work of such men as Oldham, Du Noyer, Kinahan, Baily, K^elly, Hull, Wynne, Foote, Hardman, Teall, Sollas, Hatch, and Hyland. Outside the ranks of the Survey much assistance has been obtained from the petrographical and mineralogical writings of Haughton, Scott, Hamilton, Wilkinson, von Lasaulx, Cole, and Joly ; from the chemical work of Kane, Apjohn, Sullivan, Tich- borne, Galbraith, Reynolds, Mallet, Gages, and O'Reilly; from the field-observations of Buckland and Conybeare, Harkness, Biyce, Weaver, Verschoyle, Ha rte. Close, Swanston, Callaway, and Praeger ; and from the palseontological researches of Huxley, M'Coy, Wright, Lapworth, Tate, Rarrois, and Bell. The proofs of the Petrographical part of this volume have been seen by Mr. Teall and Professor Sollas, and Mr. E. T. Newton has furnished similar assistance in regard to the Palffiontological part. Archibald Geikie, Director-General of the Geological Survey. 24th Novemfcer, 1894. CONTENTS. Page T. — Introduction. . , . ,11 II.— The Rocks. . . . . , .15 1, General Account of the Rocks of Leinster, . 15 2. Igneous Rocks of Leinster, . . .31 3. Foliated Rocks of licinster, . . .39 1. General Account of the Rooks of Connaught, . 40 2. Igneous Rocks of Connaught, . . 51 1. General Account of the Rocks of Ulster, . 55 2. Igneous Rocks of Ulster, . . .70 1. General Account of the Rocks of Munster, . 81 2. Igneous Rocks of Munster, . . 89 III.— The Fossils. ..... 95 1. General Palseontology, . . .95 2. Palseontology of Ireland, . . .108 3. List of Described, Figured, and Type Speci- mens of Fossils. . , .120 IV, — The illustrations. . . . . .128 Index. . . . . .131 i>ARf I. INTRODUCTION The collection of the Geological Survey is displayed in room No. III. East. It is limited to specimens obtained from Ireland, and consists of two parts— one illustrating the typical rocks of the country, the other the fossils contained in them. There are likewise exhibited in the gallei-y, drawings, photographs, maps, and sections, intended to illustrate the sets of specimens and to give an idea of the scenery, economic products, and geological structure of different parts of the country. The rock collection is arranged geographically, the products of each of the four Provinces of the country being grouped in close proximity to one another. The cases containing the rocks are the wall-cases along the side of the room, lettered A to G; the upright- cases placed above the table-cases in the middle of the room, marked with Roman numerals from I. to XXXII. ; and one table- ease, XXXIII., at the N . end of the room. Both numbering and lettering run from the sovith to the north end of the gallery {v. plan, frontispiece.) The collection of fossils is arranged in stratigraphical (his- torical) order, beginning with the earliest known forms of life and passing up to the most recent. It will be found in the table- cases in the middle of the room and under the windows, num- bered from 1 to 42, and in a few cases and on pedestals on the west side of the loom, numbered 42-53, proceeding also from south to north. The general order in which the specimens are intended to be studied is from left to right. The numbering on the labels of the specimens refers to the registers kept by the Survey, and is not consecutive, but it is convenient to use these numbers in referring to specimens of interest and importance, while the general sequence of remarks and description in this Guide adheres to the order of arrangement just indicated, from case to case, and from left to right. 1. THE ROCKS. It has been found advisable to arrange the rocks in three broad classes. 1st. Those which result from the cooling of the heated matter of the earth's interior, have come to the surface through volcanic activity, and have been ejected in the form of lavas and ashes, injected into or between other rocks as veins, dykes, or sills, 12 INTRODUCTION. or thrust in mass iiito other strata as uecks, bosses, or laccolites. These are the Igneous Bocks which are for the most part built up of crystalline minerals ; they are usually unstratified and unfossil- iferous. 2nd. Those which have been made out of the broken frag- ments of pre-existing rocks, worn from them by wind, weather, and water, and deposited for the most part as sediments on the sea floor. These are the Fragmental qr Sedimentary Bocks, and are for the most part built up of consolidated pebbles, sand, or mud, or of the relics of organisms ; they ai-e often fossiliferous, and almost invariably are arranged in beds or strata (bedded or stratified rocks). 3rd. Those which have usually been made by the modification or metamorphism of some other rock, either sedimentary or igneous, by the agency of heat, water, pressure, brought into action by some great earth movement, or by the in- fluence of the intrusion of igneous rocks. For want of any com- prehensive name to include the various processes which have contributed towards the formation of such rocks, the term roliated Crystalline Rocks will be used here, and it will include most of the types formerly included under the term Metamorphic rocks. They are built up of crystals which, however, are usually arranged in folia or layers which imitate in general appearance the strata of the sedimentary rocks. The Rocks of all these types are arranged and described accord- ing to the Provinces of Ireland in which they occur. A general notice of the rocks of each Province is followed by a more minute account of its igneous rocks. This description begins on page 15. The Wall-Cases. — Igneous Rocks. The igneous rocks are placed in the large wall-cases lettered A to G, beginning at the south end of the room. A study of these cases will give the student a history of volcanic action in Ireland from the earliest times up to the great outbursts which covered the north-eastern counties with vast floods of lava. The igneous rocks from Leinster are in cases A and B, those from Connaught in C and D, from TJlster in E and F, and those from Munster iti case G. The general grouping is topographical; where any marked region of igneous activity can be clearly defined its products are put together, the deeper-seated (Plutonic or Granitic) rocks claiming attention first, next the dykes and sills which may have nearly reached the surface, and lastly the ejected lavas and The upper part of these cases is occupied by maps of some of the chief areas illustrated by the specimens below, the sides by drawings, and the bottom of cases A and G by large specimens for which there is not room elsewhere. A few lai-ge specimens are also placed in case XXXIII. and some on the pedestals on the west side of the room. The drawers under the wall-cases contain duplicate specimens, or those which cannot be displayed for want of apace. TPIE ROCKS. 13 In the aiTangement of the igneous rocks the chief basis of classification is chemical composition. Four great groups of these rocks are recognized — the acid, intermediate, basic, and ultra- basic — according to the amount of silica they contain. The acid rocks contain more than 65 per cent, of silica, the intermediate from 55 to 65, the basic from 45 to 55, and the ultra-basic below 45 per cent. Each group is again divided according to the natuie of the white minerals (felspars, &c.), and black (ferromagnesian) minerals which it contains ; thus syenite is distinguished from cHorite because its most abundant felspar is orthoclase, while that of diorite is plagioclnse. Each of these smaller groups is further sub-divided according to the state of crystallization of the con- stituent minerals in the rocks — a condition which has depended largely on the depth at which the material consolidated, some por- tions having crystallized deep down below the earth's surface (Plutonic rocks) ; others near or at the surface, as in lava flows and superficial intrusions (Volcanic rocks). By this classification the plutonic, coarsely crystalline, granites, for example, which probably solidified at great depths, are separated from the micro- crystalline or cryptocrystalline rhyolites, and from the glassy pitchstones which are connected with volcanic action and have often been erupted above ground. The Upright Table-Cases. — Other Rocks. These cases will be found attached to the upper part of the table-cases, and they contain the rest of the rock collection. The plan of the cases divides the gallery into nine bays, and these are so arranged that in the second bay the reader would be surrounded entirely by the sedimentary rocks from Leinster, in the third by the foliated crystalline rocks from the same Province, in the fourth by sediments from Connaught, followed by the foliated rocks, and so on. In the treatment of each case the two lower shelves are taken together, and the whole space between two vertical bais treated as one compartment. Sedimentary Rocks. — These are arranged in stratigraphical (historical) order ; the oldest system is placed first and on the left, and is followed towards the right by newer and newer systems. The sub-division of systems is, when practicable, carried as far as that expressed on the survey maps. Within each sub-division such as the Carboniferous Slate, or Lower Carboniferous Limestone, and also where the systems have not at present been divided, the (grouping of specimens is according to districts, ranging generally from N. to S. and from E. to W. in each Province. For want of a more convenient niethod of classification two-or three different types of rocks are placed together as a third series in the remaining upright table-cases, VII. — X., XV. — XVIII., XXIII. — XXVI. ; they have, however, these important characters in common, that they are now for the most part crystalline rpcks which are, foliated, that is, have their component 14 IXTRODUCTIOX. minerals arranged in layers, and that they have been profoundly modified or metamorphoaed. so as to lose many of the characters they originally possessed. This is due either to the heat caused by the intrusion of some local mass of igneous rock as in the case ot the schists in. the borders of the great Leinster granite, oj- to some more wide-reaching cause which has brought heat, pressure, and water to bear in producing gi-eat chemical and mechanical changes in regions that have for the most part been the focus of intense earth-movement during the formation of mountain chains, as in the rocks of Donegal in cases XXIII.-XXVI. Some of these rocks have originally been sedimentary, some igneous, but chiefly intimate mixtures of the two types ; they are now, however, converted into quartzites, marbles, granulites, gneisses, and schists. The top rows of these cases are occupied by large specimens of rocks belonging to all classes, but placed here for want of space else- where or in order to enable them to be more clearly seen. They are, as a general rule, allied either in rock type or locality to the specimens placed immediately beneath. The upright-cases I,, IT,, and XXXII. are temporarily reserved for the display of recently acquired specimens or those of immediate or local interest. 2. THE FOSSILS. The Flat Table-Cases. This collection is classified according to the chief divisions or Systems of the geological record ; thus all the representatives of the life of Lower Silurian time will be found together ; on the left of them those from the Cambrian rocks, and on the right those from the Upper Silurian System. Within each system the fossils are arranged according to their zoological affinities, the whole of the Graptolites of the system being followed by the Corals, these by the Crinoids, Cystids, Trilobites, and so on in order. Although it has nothitherto beenfound possible to sub-divide the groups of fossils (or faunas) more minutely, the label of each specimen bears its precise locality and also its exact position in the geological sequence when that has been accurately ascertained ; members of the same sub-division of the animal kingdom derived from the same locality are placed as near together as circumstances will allow. The aim of the arrangement is thus twofold : firstly, to illustrate the life history of Ireland, and secondly, to keep the fossils from one locality together, so as to make the specimens available for reference and comparison by students. A general description of the anatomy of fossil plants and animals is given on page 95 of the Guide, followed by a fuller account of the more noteworthy fossils collected in Ireland, dealt with in stratigraphical order and in the order in which they will be met with on passing along the cases. The numbers used refer to the cases, to the pedestals on which individual specimens stand, or to a few framed slabs placed round the walls of the gallery, THE ILLU.STRAXIONS. 15 8. THE ILLUSTRATIONS. On the end walls of the gallery and those opposite the windows will be found a series of drawings made by Mr. G. V. Du Noyer, late of the Geological Survey, and a few by Mr. W. H. Baily. Some of these have been ti-ansferj'ed from the Royal College of Science, the rest from the office of the Survey. They are taken from different parts of the country and are intended to illustrate the characteristic scenery resulting from different kinds of rocks and rock-structures. There are represented igneous rocks, tilted and contorted sediments, moraines, eskers, boulder-clays, erratic and perched boulders, mines, and such other geological features as admit of pictorial treatment. Associated with these and also on the opposite walls are a number of large and small photographs in some cases illustrating features similar to those in the Du Noyer drawings, kindly taken and given to the Survey by Dr. Tempest Anderson and numerous members of the Belfast Naturalists' Field Club, the last having been collected for the museum bj- Miss M. K. Andrews. In the wall-cases above the specimens will be seen the one-inch survey maps illustrating some special portions of the Province from which some of the rocks exhibited below have been obtained, and at the side of the cases are smaller sketches, chiefly by Sir A. Geikie and Mr. M'Henry, taken from the published memoirs of the Survey. A few t)-pical, horizontal and vertical sections of interesting or economically important lines of country are also framed and displayed on the walls. The numbering of these illustrations begins at the south end of the gallery and runs consecutively I'ound the west, north, and east sides. A descriptive list of all the illustrations will be found at the end of the Guide, page 128, and references to them are given in brackets throughout the Handbook, those marked D. referring to drawings, P. to photographs, M, to maj)S, and S. to sections and plans. PAET II. THE KOCKS. 1.— I^BINSTElcl. I. GENERAL ACCOUNT OF THE ROCKS. The oldest known rocks in the Province of Leinster belong to the Cambrian system. They rise to the surface in rugged moor- land hills with a type of scenery made so familiar by Howth and Bray Head. The mountains, round which the southern part of Leinsler is grouped, are carved out of a mass of granite, intrusive IG LEINSTEK. into Lower Silurian rocks, at a date later than tlie Lower Silurian, but earlier than the Carboniferous, Period. The mountains are rounded moorlands, with abrupt sides, sometimes reaching an altitude of 3,000 feet, and not seldom crowned with the tors of rook so characteristic of granite areas. This barren upland gives way at its edges to picturesque, wooded, ravines and hills, of more graceful outline, and with broken and irregular summits, where the Lower Silurian strata with their richly varied pctrological character, and their interbedded and intrusive igneous rocks, rest on the granite. Where the Cambrian rocks are brought to the stirface, rugged hills again occur, ofteii varied and ' irre- gular in trend owing to the lenticular shape of the hard, ridge- making, quartzites and grits. Like a carpet the Carboniferous Limestones succeed, iilling up all hollows and levelling out the central plain of the country which is only broken where the more ancient Silurian and Old Ked Systems protrude in isolated inliers, like Slieve Bloom and Slieve-naman, or where some coal-bearing or other newer rocks rest on the surface of the Limestone, forming terraced escarpments, or the shelving flanks of the coal basins of Kilkenny and Carlow or Louth. The following table will give an idea of the general succession of sedimentary and igneous rocks in this Province. Like all other tables in this guide it is given in descending order : — Systems. 7. Pleistoceno, . 6. Trias, , 5. CarboDiferous, i. Old Eed Sandstone, 3. Upper Silurian, . 2. Lower Silurian, . 1. Cambrian, . Coal Measures, Millstone Grit, ■< Yoredale Series, Carboniferous Limestone. . l Lower Carboniferous Sandstone, Igneous Rooks. Intrusive Rooks. Interbedded Eocks? Intrusive Eocks ? Intrusive and Inter - bedded Eocks: Intrusive Eocks. In the table each set of intrusive rocks is placed opposite the latest sedimentary rocks which it is known to penetrate in that , Province. CASE III.] CAMBRIAN ROCKS. . 17 Case III. — The Cambrian System. The only known Cambrian rocks in Ireland occur in this Province. They come to the surface in three isolated regions, at Howth, about Bray, and in Wexford. (Map A; Sect. 51). The types of rocks are very much the same in all these areas and vary only in the proportion of their different ingredients ; green and purple grits (711, 912, 1227, 3476), generally much hardened, slates oi similar colours, hardened and cleaved (842, 1222, 2662, 3440), are interstratified with great lenticular patches of quartzite (1220), and quartz-rock. On the whole the coarse-grained rocks predominate towards the north, and on Howth there are bands of conglomerate (845, 6) and quartzite (3441, 2), with well rounded " pebbles," and even slaty beds containing included fragments of slate and other rocks (3443). The " pebbles " consist of quartzite, lydian stone, grits, and slates, that is the same types of rocks as occur in sitil on the hill, and it has been suggested that they are due to the breaking up of the beds soon after their formation by volcanic action. However, no volcanic fragnaents have hitherto been found amongst them, and this is in favour of an alternative explanation, that they are due to the action of earth-movement in breaking up the beds after their formation. The remarkable breccia of angular fragments which is exposed along the north shore of Howth (847), along the line of contact with the Car- boniferous rocks, is certainly due to this agency. The quartzites, when examined microscopically, still show their original fragmeutal structure, although in the field they behave almost as though they were intrusive masses. The slates and many of the grits do not split parallel to their bedding planes but at a high angle to them, the intense lateral pressure having compressed them into a smaller space. This result has been attained by the arrangement of the particles with their longer dimensions at right angles to the stress. This gives a new ' grain' to the rocks along which they ' cleave ' so as to form slates and slabby fissile grits ; unfortvmately, however, the structure is rarely perfect enough to form really good roofing slates. Still, slates for this purpose are quarried at the Devil's Glen in Wicklow and elsewhere. (1222, 3, 4, 712). Some of the specimens exhibited show that the cleavage is much more perfect in fine-grained slaty rooks than in grics, while in the latter rocks the structure is more nearly perpendicular to the bedding planes than in the former (1224, 713). Not infrequently new minerals, such as serioite, have been freely developed in the rook (1226). The rocks are also broken by other divisional planes, generally in two sets at right angles to ono another and to the bedding. This enables the stone to be quarried into great blocks with approximately rectangular svir- faces. The quartzites are traversed by innumerable, less regular, shrinkage fissures or joints, which cause the rock masses to shiver down into small sharp edged fragments and splinters under the B 18 LEI.VSTEE. [cases. IJI. & IV. disintegrating action of the frost wedge. Tiiis type of denudation imparts conical outlines to sucli hills as are built of quartzite, like the Great and Little Sugarloaf near Bray. , The only organic remains hitherto obtained from the Irish Ca,mbrian strata belong to lowly forms of life, and - are more minutely described at page 109. The fossil called Oldhami^ (2663) is of doubtful but probably oi^anic origin, and three species have been described from the localities above mentioned. Tracks and burrows of worms called Arenicolites and Histiaderma have also been found. Professor Sollas has recorded the occurrence of microscopic bodies from the slates of Howth, whicli have the appearance of being the relics of minute animals called Radiolaria, and, more recently he has described, an obscure but probably organic structure tinder the name of Fuchsia M'Henryi. On account of the folding of these rocks no accurate estimate of their thickness lias yet been made, but there is very little dqubt that it is considerable. The masses at Howth and Eray are pierced by dykes of povphyrite allied to that of Lambay Island, by diabases, and at Greystones by picrite. The only igneous mass of importance in the Wexford Cambrian rocks is a dyke of porphyrite at Cahore Point. All these are intrusive and will be fully described in the sequel (pp. 35 & 36) ; no contemporaneous volcanic rocks are known. Case IV.— The Silurian System. There are three great areas of Silurian rocks in Leinster which occupy a large extent of country, and a few minor exposures ; the Dwndallc and Slane region in Louth and Meath, the Duleek and Balbriggan area, and the great district flanking the Leinster granite which sweeps from Rathfarnham to Castledermot on the west, and from Killiney to New Ross on the east. The rocks are mostly hard, grey, green, and purple, slates and grits, but as they show considerable lithological variation it will be better to deal with each important area by itself. Fossils arc not common, but where they do occur are marine forms, like Trilo- bites, Graptolites, and Shells., The rocks were formed in a sea whose shore line has not been well made out except where the Lower Silurian rocks rest uuccnformably on the Cambrian rocks, indicating that for part of the time the latter must have, formed islands or peninsulas in the Silurian sea. .Economically the rocks are of importance in this Province. as they form the " country-rock" in which veins of the ores, of lead, silver, iron, copper, and other metals have been mined. These veins stretch in a broad belt from Croghan Kinshela to Deputy's 'Pass, and are also found in other isolated localities in Dublin and Wicklow (Sec. 11). It is also highly probable that the source from which the alluvial gold of Wicklow was originally derived may have been these rocks wliere acted upon by intrusions of granite and basic igneous rocks as near CASE IV.] SILURIAN ROCKS. 19 Oroghan Kinsliela. Slates are also occasionally quarried, in Silurian rocks as at Carnew and- in Wexford, while hone-stones are derived from them in Kilkenny;. It is hopeless at present to attempt to form an estimate of the thickness of the Lower and Upper Silurian Systems, until they have been broken up into more minute sub-divisions so that the complicated structure of the ground can be unravelled ; any estimate founded on the dip of the rocks is open to serious errors owing to the repetition of the same series again and again by folds and faults, and to the injection of great thicknesses of igneous rock. The igneous rocks are in pai-t contemporaneous lavas or asheS, but are chiefly intru- sions of a date later than the Silurian Period (v. page 33). Need- less to say. the intrusion of so much molten material has often effected importajjt modifications in the original sedimentary structures of the rock, and the metamorphisni has frequently obliterated their structure entirely and produced masses of foliated crystalline rocks ; these are dealt with on page 39. North of the Province. — The southern part of the Cavan area is just inside the Province of Leinster, but, as the bulk of the rocks and those which give the key to their structure are in Ulster, it will be better to describe them in that place (page 61). There are, however, certain grits associated with important beds of conglomerate (1443, 6), such as those of Granard, which it will, be well to notice at once. The pebbles are of gi'anite, some of them derived from the mass of Crossdoney (y. page 76), associated with lydite, grits, and fragments of a chert lithologically like that recently foiind by the Survey in sitti in Tyrone ; these frag- ments, however, yield Radiolaria like the cherts found in the Lower Silurian rocks of South Scotland and on the N.E. coast of Co. Down, at Donaghadee. These conglomerates are likely to be of Upper Silurian age, but on the maps they have not yet been distinguished from the Lower division of that System. The Area of Louth and Meath (Map B).— Silurian rocks stretch away to the south and south-west of Dundalk, Dunany Point, and Clogher Head, from Louth into Meath. Eecent researphes by Mr. Clark have shown that at least four important horizons can be recognized in these rocks by means of the Grap- tolites and other fossils which they contain ; the Llandeilo and Caradoc Series of the Lower Silurian System and the Llandovery and Tarannon Series of the Upper Silurian ; thus, in descending order : — ■ Tarannon Series, . Salterstown, near Dunany Point. Llandovery Series, . Mooretown, Kellystown House, W, of Tullyallen. Carcbdoc-Bala Series, Collon, Slane, an4 Grangpgeeth,, Llcmd&ilo Series, , S. and S^E. of Ardee, near Newtown Fortescue, and Harliustown. b2 20 LElNSTfig, [case l'^. I'lOhl tliis it will be seen that the Lower and Upper Silurian rooks are closely interfolded together, so that the -work of dis- entangling them on the maps over large areas will be one of time. About Dundalk and Dunany Point the rocks are hard, greenish gt-its and slates, much indurated. Near Slane daik, carbonaceous shales (1286) are interbedded with sheets of andesitic lava and ash, which probably represent the great Afenig or Lower Llandeilo eruptions of North Wales and the English lakes, as a Graptolitic favina of that date has been found in the associated sedimentary rocks. It is, however, not impossible that some of the volcanic rocks may belong to the period of the Bala or Caradoe eruptions, as Bala fossils are found in close proximity. These are followed by grey quartzose and felspathic grits and shales of Bala or Llandovery age. There are many intrusive sheets (or sUls), dykes of diabase, and lamprophyre (or mica-traps), and intrusive bosses of augite- syenite in the Slane district (v. page 36). Passing along the strike of these rocks towards Clogher Head to the north- east, coarse and fine indurated grits occur, possibly of Llandovery date, which are saturated with dykes of lamprophyte and diabase, and are frequently much metamorphosed by them (3518, 9, 3546). The igneous rocks of these areas are placed with the other igneous rocks of the Province in case B, and are described on page 37. Duleek and Balbriggan Area (Map B). — The lowest rocks of this area are the lavas and ashes of Bellewstovvn, which are banded with clay-slates (718, 716), such as are quarried at Balbriggan, and black shales (914), full of Didymograpius Murchisoni, and hence are of Lower Llandeilo or Upper Arenig age. It is not a little interesting that the composition of the igneous rocks of this date in Ireland corresponds very closely with that of rocks of similar date in England and "Wales. In this region again Upper Silurian rocks bearing Jlonograpius are closely interfolded with thosie of Lower Silurian age. On Lambay Island and at Portraine there are a few bands of limestone from which many fossils, chiefly Corals, Brachiopods, Trilobites, and a few Graptolites of Silurian genera have been obtained. On Lambay Island occurs a conglomerate (672, 684, 685) containing pebbles of Silurian limestone embedded in a matrix from which fossils of the same age can be extiacted ; this has probably originated from the breaking up of a newly- formed limestone by the volcanic action which was rife at intervals during this period. The rocks are intruded upon by sills and dykes of porphyrite, one of which is the beautiful ornamental "porphyry" of Lambay, with its green porphyritic crystals of felspar embedded in a dark-green matrix. Intrusive rocks of other types, such as diabase and lamprophyres, are also found at Duleek {v. page 37.) At the Chair of Kildare are found the well-known pink and grey, crystalline, fossiliferous, limestones, here interbedded with red and dark-grey fissile shales several hundred feet thick, penetrated by igneous rocks of the .CASE IV,] SILURIAN ROCKS. 21 Lambay type, and covered by grits recalling those of Meatli and Cavan. A la cases 3 to 13, Cavan. A large series of fossils from these rocks will be found in Flanks of the Leinster Granite (Maps A and B). — Proceeding further soiith the rocks become more uniform and finer-grained, slates (j\l), green, purple (1238), and black in colour with occa- sional fine grits (1234) and limestones (877) taking the place of coarse grits and sandstones. These begin to undergo changes within a mile of the outcrop of the granite, and the metamorphism increases as the junction plane is approached (v. cases VII. and VIII.), so that eventually the slates become highly micaceous, crystals of andalusite, and at times garnets make their appearance, and eventually the rock passes into a mica schist. Much of the beautiful wooded scenery of Wicklow, which affords such a Avel- come and striking relief to the rounded granite moorlands, is duo to the varied character and metamorphism of these rooks. Throughout their whole extent the sediments are interbedded with ashes and lavas (2664) and seamed with dykes, sills, and other intrusions of an exceedingly varied set of rocks, granites and microgranites, felsites, diorites, dolerites, epidiorites, and picrites. These igneous rooks are often crushed so much that new minerals and structures have been formed in them, making fclsitic and hornblendic schists, while the sediments are frequently cleaved and contorted (738, 9), the puckering sometimes passing down to the minutest and even most microscopic scale (1230, 1) ; all these changes indicate clearly the intense lateral pressure to which they have been subjected. Fossils are abundant in these rocks in Wicklow and Wexford, and prove them to be of Lower Silurian age. It is interesting to note that they occur nearly always, in fact almost solely, in the ash beds. Indeed this is true of the Silurian rocks throughout Ireland, as no fossils but Grap- tolites are found in any abundance except in association with contemporaneous igneous rocks. The Silurian rocks of Slieve-naman, Slieve Bloom, and Mount Mellick are coarse greywacke grits (1593) and hard, close slatfs (1595), more or less cleaved, from which, however, in Leinster no fossils have yet been recovered. Mr. Kinahan has recognised three divisions of the Silurian Sys- tem in Wexford. The lowest is a Dark Shale Series comparable with theLlandeilo of Wales, and containing thi-ee seams of anthracite and some graphite. This is followed by his Ballymoney Series of red and purple shales, grits (878), and ashes (715), with eruptive rocks and Caradoc-Bala fossils, and this in turn is succeeded by a series almost devoid of gi'its, but with Grey and Oreen Slates, useful for building purposes. Possibly this last series may repre- sent the higher part of the paradoc or even part pf the Upper giluriJi-n System. 22 LEINSTEK. [case IV. Case IV. — The Old Red Sandstone. This System of rncks occupies a comparatively smalL area in Leinster, generally a mere fringe to the Silvirian ti-acts, but becomes of greater importance towards the South of the Province. The rocks appear to have been formed in fresh-water lakes, some of ■which were continuous with those of Scotland. They are of uniform and somewhat monotonous character, red, purple, brown, and white sandstones, with intercalations of similar colo'ared shales and conglomerates in whiph pebbles of vein quartz predomi- nate. Two or three small tracts in Longford answer to 'this description (682), atid are here unconformable to the Carboiii- ferous rocks above and the Silurian beneath. On Lambay, at Donabate (sec. 51) and Portraine, small patches of pink sandstone and conglomerate, not nlore than 300 feet thick, have been mapped as Old Red Sandstone; salmon-coloured sandstones, puce conglom- erates, and purplish shales fill the hollows of deniided Silurian rocks to the north of the Chair of Kildare, while there are red quartzose conglomerates near Newcastle and Rathcoole ; these rocks are little more than a local base to the Carboniferous System. Omitting the small inliers, all but covered up with newer rocks, which occur to the south and south-east of Athlone, where the rock is unconformable to both Silurian and Carboniferous Systems, the Old Red Sandstone begins to assume real importance round the Slieve Bloom and Devil's Bit Mountains. A basal breccia is followed by white, dull reddish, purple, or speckled sandstones and grits (1597, 8), frequently containing plant-remains (724), and amounting to 800 or 900 feet in thickness. Equally thick and important are the same rocks in Kilkenny where an iipper division of yellow sandstone (The Kiltorcan Beds) is of interest because it has yielded fossils including plants like Adiantites and Sphenop- teris (725), a freshwater mussel Anodonta Julcesii, Crustacea, and Fish {v. frame 45). In Wexford a purplish grit and conglomerate has been mapped as Old Red Sandstone. This formation is of little economic importance. It forms the border tract of liilly ground between the mountainous Silurian country and the flat plain of Carboniferous Limestone Cases V. and VI. — Carboniferous System. (Map B ; D. 18). — Much of the area of Leinster is occupied by rooks belonging to this System and chiefly by the lower part of the great Limestone; Series which, however, is here and there covered by the higher divisions of the System, or by a capping of the highest Carboniferous rocks in Meath and in the coalfield of Kilkenny. The divisions usually recognisable are the following, but it is not always that all of them can be identified, as some thin out or have been removed by excessive denudation, while , CASES V, & VI.] CARBONIFKROUS ROCKS. 23 it is sometimes imijossible to draw lines between the different divisions of the Carboniferous Limestone. 8. Jliddle Coed Measures. 7. Lower Goal Measures. C. Millstone Grit. 5, Yoredale Series. i Upper Carboniferous Liinesionei 3. Middle „ ,. 2. Lower „ „ 1, Lower Limestone Shale or Basement- Beds, The lowest rocks contain marine forms of life and indicate the entrance of the sea into the Old Eed Sandstone lakes, while the suc- ceeding masses of limestone indicate that the sea deepened consider- ably and swarmed with Shells like Producta and Spirifera, with Corals like Lithosttoiion, Zaphreniis, and Michelmia, which Some- times built veritable reefs, or with an immense abundancfe of Crinoids, like Actiiiocrinus^ Poteriocrinus, &c., w-hos6 remains build up great thicknesses of calcareous rook. Layers of shale and beds of impure limestone show that powerful rivers and currents could still bring sediment from the not very far-distant land, and eventually the whole basin became shallower and covered by river deltas in which, at first under marine conditions and later under fluviatile conditions, the Yoredalo Series, Millstone Grit, and Coal Measure.? were deposited. Judging by what is left of the Measures it does not appear that the conditions were ever very favourable for tJie growth of coal ; the seams ar6 few in number and poor in quality, and the persistent denudation of sub- sequent ages during which Ireland stood above water has deprived her of what little coal she had. The famous black marbles with white shells from Kilkenny and Carlow are quarried in the Cai-boniferous Limestone, which also yields road metal and excellent lime, both ordinary and hydraulic, the latter when it is not very pure but loaded with fine particles of clay or silica. The crystalline limestones furnish good but rough building blocks, the darker, argillaceous limestones, though widely u«ed, are less satisfactory ; the crinoidal limestones are used for building and also for marble. The grits and sandstones provide freestones much used locally for building and flagging, a.nd, when rough and gritty for millstones, while, the Coal Measures give coal, iron, fire-clays, and clays useful for pottery. Occasionally small quantities of lead and zinc are found in the veins which penetrate the limestone, while beds of hseniatite and even clay-ironstone occur sometimes in the same rock. , , In Leinster the limestone area is usually flat or gently undu- lating ground largely covered by bog and devoid, except in' a few places, of scar'ps or any important physical features ; the Yoredale ^24 LEINSTER. [cases V. & VI. Beds and Millstone Grit, hj the alternation of liard grits or lime- stones with soft shales, form parallel valleys and ridges ov escarpments, such as those seen round the Leinster coal-field, prominent amongst which is the abrupt scarp of tlie Millstone Grit ; the Coal Measures occur in areas which are basins in pliysical contour as well as in geological structure. The thickness of the various members depends on local circum- stances, and difiers so much from point to point that any estimate ot total thickness would not be of much nse. Where fully developed, however, the System can hardly be less than 6,000 feet thick. The only igneous rocks are the intrusive dykes, almost certainly of Tertiary date, found in Louth and Meath, and the interesting series of lavas and ashes about Phillipstown which may be com- ])aved with the rocks of Limerick on the one hand and with those of Derbyshire on the other (v. pnge 38). The Lower Limestone Shale or Lower Carboniferous Sand.- stone. — This division is usually thin and unimportant in Leinster, the subsidence of the land and its lakes beneath the Carboniferous Sea having been somewhat sudden and rapid. There are beds of yellow sandstone in County Meath, occasionally traversed by basalt dj'kes belonging to the great Tertiary volcanic group, and fine grained siliceous c/rits (14.49) in Longford. In tlie South, in Wexford, the Carboniferous System is heralded by beds of barely consolidated conglomerate (721, 2) made of pebbles derived from the granitic, silurian, and cambrian rocks on which they rest. But in the central region, wherever the lie of the rocks allows their base to be seen, it consists of dark calcareous sliale v/ith bands of thin flaggy limestone (IGOO) which increase in number and importance in the higher part of the Series. Sandstones are rare in this central tract where the whole thickness rarely exceeds 100-200 feet. The Lower Carboniferous Limestone — The lowest division of the great Limestone Series is the foundation of the Central Plain of Ireland and its wide-spread bogs. The rock is usually grey, or , bluish-grey in colour (729), often fossiliferous (1299, 1 602), and more or less crystalline in texture (1602). A few beds of laminated micaceous sandstone occur in Louth and Meath (1298), and many sand-beds in Wexford where the limestone is itself sandy (852, 864, 733, 915), but in the central tract the limestone is pure and frequently displays oolitic structure as at Edenderry (732), near to , which the rock is dove-coloured and made up of globular bodies consisting of radiating crystals of calcite (carbonate of lime), generally accreted round some foreign substance such as a chip of shell, a crinoid stem, or a grain of sand (731, 3477). In West Meath a grey limestone, which takes a high polish, is quarried as a marble. In Dublin, King's County, and Carlow portions of the rock have been transformed into dolomite, that is limestone con- taining a variable but frequently large percentage of carbonate of magnesia. In Queen's Popnty the limestone contains bands of chert. CASES V. & VI.] CAEBONIFEROUS ROCKS. 25 When this Limestone is not separated from the older rocks on ■which it rests by any intervening deposit, its lowest beds, as at Skerries, contain, pebbles of these older rocks. The thickness of this Stage is about 1,000 feet in the centre of the Province, and about 200 feet more in Kilkenny. The Middle Carboniferous Limestone, or " Calp '' as it is some- times termed, is usually a dark-coloured or black limestone, shaly or flaggy, and interbedded with dark shales and even occasional sand- stone beds. The individual limestone bands are not constant in character or thickness for any considerable distance. About Philipstown there is a volcanic area dating back to Carboniferous times, bands of basic ash containing fragments of limestone, and intrusivelimburgitesand basalts, occurringin tho middle limestone, which is penetrated by coarser grained basic rocks. The igneous rocks are apparently covered by the highest member of the Lime- stone series. In Queen's County a bed of yellowish or brown crystalline dolomite occurs at the summit of the Sei-ies. Bands of chert, usually grey in colour, are of not infrequent occur- rence (935, 675). Fossils arc not so common in this group as in the beds above and below, and -where they occur are usually large Produotce and Corals. The thiokne.ss of the Stage varies from 600 to 800 feet, but there is a general tendency for it to become thinner towards the west. The Upper Carboniferous Limestone is not always separated from the Middle, this being the case when the former division loses its purity and becomes more intermingled with sedimentary material, so as to approach the calp in composition. This is the case in the Dublin. district(Map B., Sec. 51), where bothstages consist of grey thin bedded limestone with black shale partings ; often it is darker in colour and much veined with caloite (1302), and some- times magnesian limestones occur ; these are frequently cavernous, as though the rock had shrunk in volume during its metamorphism, and crystals of bitter spar are often found lining the cavities (728). Those beds which are not far from the granite near Dublin Bay, contain lumps derived from it, often as much as 1 8 inches in diameter, together with fragments of schists and other rocks from the flanking Silurian chain (726,730). A special series of these has been collected by the Director of the Mnseum and placed in the neighbouring room (IV. East), where he has illustrated them by a set of similar stones carried great distances from the shore in modern times by such agencies as sea-weed, floating wood, ground ice, and other forms of floating ice. In its characteristic aspect the Upper Limestone recalls the lower stage; it is a light grey (1315), shelly (851), limestone, iisually sub-crystalline in texture (2667), and often oolitic (1608, 1619, 1621). When this structure is present, as in West Meath and King's County, the rock forms an admirable building stone. In Kilkenny, where the Stage is 1,500 feet in thickness, and also 26' LEINSTER. [cases V. & VI. elsewhere, there are abundant beds of chert, -which ,are sometimes 30 or 40 feet in thickness, and vary from dark grey (674) to black '(727) ill' colour (fi. D. !22). The passage from limestone to ehfert is quite gradual, the rock becoming more and more siliceous until at last it consists of almost pure silica with a splintery or conchoidal fracture and horny or resinous lustre. From the abundance of spicules and skeletons of sponges displayed in micro- scopic sections of the chert it has been concluded that the silica was derived from this source and that after partial solution it ■Was .redeposited and aggregated in those portions of the limestone ■which were already exceptionally rich in these fossils. ' The lime- stone is 6ften made \ip wholly of fragmental crinoidal stems, and is tisiially rich in fossils.' Dolomites occur everywhere ; ■they ai-e white or yellowish grey in coloiir, finely crystalline, and exhibit n!b signs of lamination or bedding ; they occur as beds, as plates and masses related in position to the joints traversing the rock, and even in a dyke-like form running uninterruptedly for many miles. It has doubtless been formed by the passage, through the joints and beds of the rock, of water bearing magnesiain salts in solution, which has replaced pure carbonate of lime by a double carbonate of lime and magnesia. The Yoredale Beds, or " Shale Series "• as they are sometimes designated on the maps, mark the close of the limestone-forming period. They are generally shaly in character, especially in the lower part, the few bands of Ihnestone being thin, black, and impure ; occasional bands of iron-ore and even worthless coaL seams occur in the Series. Towards the North, in i\Ieath and Louth, there ai-e 300 or 400 feet of dark shales and thin limestones underlying the Millstone grit, and in the eastern counties a few outliei's (Sec. 51) formerly mapped as coal measures, would nowprobablybe classed with this Series. The rocks consist of 500 feet or so of hard, dark, splintery shales inter- stratified in some places 'with thin grits and flagstones. Under the Kilkenny coalfield the black slaty shales and splintery mudstones frequently weather out into spheroids. The series here is about 500 feet in thickness and contains hard grey sandstones "with a few beds of flagstone (853), and some ironstone seams of poor quality (1243). The Millstone grit, or " Flagstone Series," is a persistent group of hard, thick, sandstones, grits, and flags, occasionally yielding plaiit-remains but rarely other fossils, 500 feet thick at the north of the Leinster coalfield but thinning away towards the south and east. In Louth the series of coarse, massive, micaceous quartzose grits and conglomerates under the coal measures is about 200 feet thick, while in the south of Meath grits and shales -with thin coal-seams (1317, 676) rest on the Yoredale beds already described. The Lower Coal Measures, or " Gannister Beds " of Louth con- tain quartzose gfrits (1336) and beds of sandstone (1333) which are CASE VI.] TRIASSIG ROCKS. 27 frequently coloured purple or red, probably by the agency of water penetrating from the Permian or Triassic rocks above them. Those of Meath are fine grained, white, brown, or mottled Sandstones with at least one seam of coal 1 foot thick. The measures of the Kilkenny coalfield (Sees. 46 and 50) are hard, grey, and mottled brownish grits penetrated by stigmarian rootlets, ^recteys, and brickclays, shales (854), and occasional bands of ironstone. There are 4 seams of coal, varying from 3 feet to 6 inches in thickness. A few marine fossils are found in this division (Sec. 51). In the Middle Coal Measures of the same region there are 6 seams of coal, the four highest of which are now worked out. These are thicker and vary from 5 feet to 1 foot in thickness, and their fossils are related to modern freshwater types. A large collection of Amphibia has been obtained from the Jarrow seam, the lowest member of the stage. iThe interbedded measures are much the same as those of the lower Stage (855). The whole of the coal measures is about 1,600 feet in thickness (Sec. 51). Case VI. — The Triassic System. (Map B.) [n Leinster there are no Permian rocks, so that the Trias is the only system occupying the enormous gap between the Carboniferous period and the deposits of the Pleistocene period which succeed : even this System is very poorly represented by a portion only of its two Series the Bunter and Keuper, and this deposit is not found further South than the northern part of Meath. The Carboniferous rocks had been folded and their surface eroded before the Bunter beds were laid down in the lakes formed on the denuded surface of Carboniferous and older rocks. The Bunter is represented by a soft light-red, flesh-coloured, or pink, sandstone bright in colour and well laminated. The Keuper. — The Bunter is followed, in the neighbourhood of Xingscourt by the "Keuper Series, thin bedded, laminated, brownish sandstones with bands of grey and red shale; then comes a considerable, but unknown, thickness of red and grey shaly marl containing beds of gypsum (1330) which have been at times worked in this neighbourhood. The Keuper clays ai'e used for brick-making. Case VI.— The Tertiary Group. Resting on the "solid" rocks of Ireland' there are usually found " superficial " deposits laid down by the agency of the sea or freshwater, by the action of ice, or even by some cause capable of forming deposits in the air. It is extremely difficult to classify these satisfaqtorily and even in many cases to ascertain their 28 LEINSTER. [OASE VI. relative age, as so many different agencies were at work in different localities — the sea on the shore, the lake or river inland, and the glacier on the mountains. Again, during oscillation of level a homogeneous deposit might travel inland or out to sea and appear to be a continuous layer, while, as a matter of fact, one end of it must, of necessity, be very much older than the other. Roughly, the deposits may be classed as pre-glacial, glacial, and post-glacial with reference to the great extension of ice over the country iu the glacial period. Case VI. — Pre-glacial Eocks. Pipe Clays. — To the IST.W. of Roscrea a small patch ai pipeclay occurs. It is similar to that of Caher, in Tipperary, of which a description will be found on page 88. " Manure Gravels " of Wexford. — This series of deposits under- lies the boukler-clay in Wexford. The lowest beds are fine, clean, sharp sands, without stones or shells ; these are followed by beds of finely comminuted shell-sand, in which ninety species of shells have been found ; the sections are completed by fine ijravel with shells, which are occasionally perfect but are generally waterworn and broken. The majority of the shells are of species which are still living on the Irish shores, but a certain proportion are such as inhabit the Mediterranean and southern seas, while a few are extinct. They indicate a warmer climate than thei present ; judging by the resemblance of the fauna to that of the Pliocene beds of St. Erth in Cornwall, the gravels must be of Pliocene date, but more recent than the St. Erth beds. Mr. A. Bell, who has investigated the deposits, concludes that the Wexford gravely are succeeded in date by those of Ballybrack ; the latter again by those of the Wicklow mountains, to be immediately described. Case VI. — The Pleistocene System. The Lower Boulder-Clay. — This deposit presents us with the record of the great Ice Age in Ireland. Although different observers rarely agree upon any one theory to account for its origin all are agreed that it has been made by ice in seme form, whether ice-sheets on land, shore-ice, or icebergs. The deposit, known as boulder-clay, is a stiff tough clay, usually red, brown, or blue in colour, and made up of material denuded from local rocks. It is genei-ally unstratified but occasionally stratified and. is full of rounded pebbles or angular blocks of rock, often of very large size, set pell-mell in the clay without any sort of arrangement (D. 35). These blocks are often polished and smoothed, striated and grooved, as though they had been held firm in the grip of moving ice and slowly dragged over the surface of rock (1244), and as the rock on which the boulder-clay rests is usually polished and grooved in a similar way it is clear that the Case Vi.] pleist'ociine rocks. 29 stones have been polished by the rook bed over which the glacier has moved. The direction of the grooving, together witli the direction in which blocks of stone have been carried, show the direction of ice movement to have been on the whole from N.W. to S.E. in Leinster, though this direction is disturbed where mountain masses served as barriers or independent centres of ice dispei-sion. The main snow-shed which gave birth to the ice of, at any rate, this part of Ireland is supposed to have stretched from Belfast to Galway Bay. The clay is irregularly and some- what capriciously distributed but has a tendency to occur in ridges or drumlina whose long axes coincide with the direction of ico flow, or in sheets tilling up valleys and lapping against the sides of the mountains, even to a height of 1400 feet. Amongst the far travelled boulders found in tlie Leinster boulder-clay may be mentioned Antrim chalk and flints, granites from Mourne and Newry, rhyolites from Forkhill, and riebeckite-microgranite like that found at Ailsa Craig. The boulder-clay passes up into the succeeding deposits of sand and gravel by the alternation of seams of clay with beds of gravel. Contortions, irregular junctions, and the dropping of sand into pipe-like hollows of the boulder-clay may pei-haps be accounted for by the melting of blocks of ice contained in the latter. Fossil shells are occasionally to be found in the boulder-clay, sometimes whole and unbroken but more usually fragmental and even polished and striated like the rest of the derived blocks in the clay. The Sands and Gravels, sometimes called the " Corn Gravel," "Limestone-Gravel or -Drift," from the profusion of limestone blocks in it, sometimes the " Interglaoial Sands," are seen in such sections as that of Ballybrack and Killiney to rest on the Lower Boulder- Clay, and sometimes to be covered by the Upper Boulder-Clay. The deposit consists of irregularly bedded sands and gravels sometimes containing large boulders, which would indicate that ice-action of some sort had not entirely ceased. Many of the boulders and pebbles consist of limestone, but other local rocks are present like Cambrian sandstones, quartzite, schist, lydites, and igneous rocks. SoUas and Praeger have described pebbles of the subjaoiait boulder-clay in the gravels. They contain shells, sometimes in abundance (v. p. 119), which are mostly of northern types but seem to indicate a slightly warmer climate than those found in similar gravels at Moel Tryfaen in North Wales, The gravels with their shells are found at Ballyedmonduff, Caldbeck Castle, and elsewhere, to extend upwards on the flanks of the Wicklow niounlains to such heights as 1,250 and 1,300 feet, and it is very difficult to account for them in such situations with- out supposing a great submei'gence to at least this extent. Occasionally the gravels are converted into a solid I'ock by the deposit of salts of lime or iron. The Upper Boulder-clay is of much the same character as ■ the Lower, butj probably ■ owing to extensive denudation, is 30 LEINSTER. [case VI. somewhat rarely met with. It is a reddish, stiff, clay with boulders, and seams of sand and silt. In Carlow it is 90 feet thick in places. The Esker Gravels. — These deposits have sometimes been con- sidered the equivalent of the mid-glacial sands and gravels, but are more generally thought to be rather later in date. It is of course quite possible that they may be of several different dates, and probably all so-called eskers may not have originated in the same way. The eskers are long mounds, frequently of considerable height, devious in direction and extending over ilat country, along valleys, or even at times across the older physical features of a district. In the centre of Ireland, extending from Connaught into Leinster, they are numerous and gigantic, being sometimes 50 or 60 feet high, resting on a base 100 to 200 feet wide, and as mud as twenty-five miles long. A group of these eskers at Coney Cairn is represented in Mr. Du Noyer's drawings Nos. 37 and 38. The mounds are made up of fine gravel with a stratification which generally follows the outline of the mound. Shells are occasionally met with but are distinctly rare, a thing which might possibly be attributable to the ease with which water percolates through the gravel. No perfectly satisfactory theory has yet been advanced to explain the origin of the eskers. While some observers believe them to have originated from deposition under the influence of marine currents as sand bars and banks during submergence. Professor Sollas and others regard them as the deposit formed by the superficial drainage of the ice sheet, the rivers which traverse the surface or flow at the bottom of the ice and which, carrying mud, sand,, and gravel with them, must deposit it under the ice, or on it to be afterwards let down as the ice melts. One thing is certain, that the glaciation had not ceased when the eskers were formed, for their surfaces are often strewn with erratic blocks of stone which may be of considerable size. Numerous erratic blocks are found scattered over the surface of the ground in Leinster and the other Provinces, not necessarily in direct connexion with any glacial deposit, and they may belong to any part of the glacial period (v.D, 36). The esker gravels of Kildare are sometimes cemented into a conglomerate (737). Local Moraines also occur in the Province. They have clearlv been formed near the close of the glacial period by ice fields and local glacier systems of small extent occupying the chief mountain areas, such as the Carlingford and Wicklow mountains. Upper and Lower Lough Bray are dammed by such moraines, and a beautiful group of local moraines has been described and figured by Kinahan on Mount Leinster. Raised Beaches.— These, consisting of material similar to a modern beach but at a level beyond the reach of the highest tides of the present day, are fotmd stretching along the coast line in various iplaces. The neck which unites Howth to the mainland is one of CASES VI. & A.] IGNEOUS ROCKS OP WICKLOW, &C. 81 them, and relics of a similar beaohj-eemented into a conglomerate by aragonitea form of crystalline carbonate of lime, occur along the store of Dublin. Bay by Salthill and Kingstowa (790). . (The Estuarine Clays of Clontarf which contain marine shells are believed by Mr. Praeger to be a deeper- water deposit. of the. same age. As the rivers, during a period of submergence snob as the terraces and clays indicate, would necessarily flow at a higher level than at present, it is highly probable the high, level gravel terraces which fringe these rivers may be of about tihis dateysiich gravels ^re sometimes converted into solid stone in ' Wexford, Prom an economical point of view the old gravel terraces and alluvia of the rivers which drain the northern slopes of Croghan Kinshela are very important, as it is from th6m that the alluvial gold of Wicklow has been obtained, and hitherto all' attempts to trace this gold to its source have been fruitless. Its association with fragments of heavy minerals such as magnetite, hsem'atite, tinstone, copper pyrites, galena, topaz, and garnets seems to show that it has been worn down from veins in igaeous and metamorphic rocks. ■•''.) Peatbogs. Over the interior of the Province these are of .great extent and value. They are often of great depth, and frequently rest on beds of blue, shelly marl, con.taiaing freshwater and lacus- trine shells, similar to those in existence at the present day. Mr. Clement Reid finds that some of the Megaceros marls are mainly composed of Cliara, with other water plants. Other modem deposits are blown sands, river alluvia, and intakes or deposits formed by the filling up of lakes, low valleys, or arms of the sea by warjiinr, the deposit of mud carried down by rivers in flood ; in limestone districts masses of travertiyie or carbonate of lime are sometimes deposited by the calcareous springs (73-5). ' 2.— THE IGNEOUS ROCKS OP LEINSTER. ■: V' Case a.— Dtolin, Wicklow, and ' Wexford, (Maps A. and B. ; Sec. 50). — One of the grandest areas- -^f Igneous rook in Ireland is that of the Leinster granite and its flanking masses, which sweep from the south side of Dublin Bay to the boundary of Waterford, forming achaija of '-lumpy, w.oolpack,- hills " sometimes attaining a height of' over 3,G0O feest, ; The main chain is a, great mass of Granite 10 miles Ion'" and ,20 miles broad at its widest part. It is a true Granite coarse in grain, and distinguished by its large crystals of musco- vite, a white potash mica .(a monoclinic, unisilicate of alumina and potash). Biotite and muscovite )vere the first of the so-called essential minerals to crystallize, and they were followed by pla- gioclase felspars which vary from albite (triclinic unisiUcate of soda) to oligoclase (triclinic unisilicate of soda and lime),, these by quartz (hexagonal silica), while the last constituent to take' the, solid form was generally microcline , (a triclinic potash felspar, or unisilicate of alumina and potash, allied to orthoclase in com- 32 LSiNsTgiJ. [cAsiE A. position). A large series of coarse and fine-grained types, obtained from all parts of the Province, is exhibited. Occasionally biotite (a magnesian mica) is present in considerable quantitj'' (1917, 1926, 1928, 1931), rarely to the entire exclusion of the mus- covite (1927, 2030) when the rock must be called granitite. Porphyritic felspar is well shown in the large specimen 1216. Many other minerals are present as minute inclusions j zircon (tetragonal unisilicate of zirconia), titanite or sphene (monoclinic subsilicate and titanate of lime), apatite (hexagonal phosphate of ,lime), and rutile (tetragonal oxide of titanium) ; tourmaline or schorl (a hexagonal complex subsilicate of soda, potash, magnesia, lime, and alumina) is present at times (1945) either in the body of the rock or coating its joints (1946, 7). Other minerals mentioned by Mr. R. H. Scott are beryl (hexa- gonal bisilicate of alumina and beryllia), fliior (cubic fluoride of dime), orthite (monoclinic unisilicate of lime, iron, alumina, and ceria), iron and copper pyrites (cubic sulphides of these metals), and galena (cubic sulphide of lead), with cordierite or iolite (orthorhombic unisilicate of alumina, magnesia, and lime) dis- covered by Joly. At Tinahely large crystals of spodumene (monoclinic bisilicate of lithia and alumina) occur, and these are often converted iuto a pseudomoi-ph which has been named killinite "(a hydrous silicate of alumina and lithia) (1951). Veins con- •taining garnets (cubic unisilicates of alumina or iron with lime or magnesia) also occur (1948). When tlie crystals of the essential minerals are large and the rock forms a coarse pegmaiite, that is, one in which the quartz is intergrown with the felspar giving rise ■ to the appearance suggestive of Hebrew writing which has caused the rock to be called graphic granite, the muscovite often occurs in plumose masses (1213, 1950) which are very beautiful. The granite has been much used for buildings, and many of the footpaths in Dublin are paved with granite flags. Kaolin or china-clay (silicate of alumina) has been quarried at Baltinglass, where it results from decomposition of the felspar due to the loss of its potash (2676). Ores of iron and manganese have occasionally been found in the granite. The granite is traversed by veins or dykes of apliie, a rock made , up of quartz and felspar, with little or no mica ; these are well seen on Killiney Hill and in the railway cuttings below it (1952-3, 2678). Where it has undergone intense pressure, and this is , especially the case near its margin, it has become foliated ; that is, its minerals are arranged in layers. A good example, with layers of mica, is seen in 1956; others are seen in 1935, 1957, and specimens, in which the rock is undistingviishable from a gneiss, are found at Graigue-na-managh in Carlow (2685.) Near these are placed a few specimens showing patches of sedi- mentary rock contained in the granite (1960), or the junction of granite with sediments (D. 21), which are in both cases converted into mica-schist (1958, 2679), a rock composed of alternate leaves of quartz and mica f^vide page 39). . dASK A.] IGJJEOUS llOdKS OB* VVIOKLOW, kc. 8S The Leinster granite always contains a considerable percentage of soda as well as potash, and in studying the veins (or apophyses) which it sends out into the surrounding sediments, and the innumerable smaller masses evidently connected with ' it and derived from the same source, it has been found that the amount of soda gradually increases until it becomes double that of the potash. These rocks have been described by Professors Haughton and Sol las. They are usually so much finer grained than those of the main chain as to deserve to be called microgranites (1961, 1981), and they even pass down gradually at their edges and extremities into qvartz-fehites, in which the larger porphyritic crystals of quartz and felspar, and sometimes mica, are embedded in an amor- phous paste (1964, 2688). They ai-e somewhat less acid than those of the main chain, and are frequently rich in biotite (1937, 1944) ; others of them contain hornblende (monoclinic bisilicate of magnesia, lime, and iron, with alumina) (1968), especially those of Croghan Kinshela (1942), and here the rock often consists of inclusions (segregations?) of dark rock involved in a network of light coloured veins (1979). The striation of the plagioclase felspar is frequently observable in hand specimens of these rocks. They have been injected as sills, for the most part roughly parallel to the bedding of the surrounding sediments, which are much metamorphosed by them, and they are to be found flanking the granite throughout almost its entire extent. The age of the great granitic group of rocks has not been pre- cisely determined. It is a curious fact that it is not known to come into contact with the Cambrian rocks, although it is intrusive into Lower Silurian rocks ; its date is therefore later than the Lower Silurian period, and certainly earlier than the Carboniferous, for fragments broken from it occur in a limestone- conglomerate at the base of the Carboniferous Limestone of Dublin (vide page 25), It may therefore be either of Upper Silurian or Old Red Sandstone date, and as the latter period was one of great earth-movement we may reasonably place the date of its irruption in the Old Red Sandstone period. Parallel with the edge of the chain and outcropping along the strike of the strata, are innumerable bands of different varieties of fdsites (fine grained rocks with the same chemical composition as granite), and other rocks. The bulk of these are lavas which have been poured out and interbedded with the Lower Silurian sediments amongst which they are found. They have been disturbed with them also, and have frequently been crushed, and have acquired a brecciated, flaky, or schistose structure in con- sequence ; examples of all these structures are placed in the next division of the case (1985, 6, 1215, 1991). The felsites are acid in composition, and are allied to those found in the Lower Silurian sti-ata of North Wales. They vary from quartz porphyries or quartz fdsites, which contain porphyritic crystals of quartz, to those which contain quartz only in a microscopic state ; orthoclase- felsites without individualized quartz (2700) but with porphyritic C 34 LEINSTER [case Ai crystals, ^of ort)iocla,§p (a jn6iioclinic .unisilitate- of alumina ; and potash) (J 994, 1996) also occur, and Dr.. Hatch- h&s detiSKmined the e?:istenpe of felsiteg rich in sqida, felspars (oligocIase)i, and Jiencej . cgtllfed ^oda-Jelaites or, Mratophyres. •■. As. .an example of thSilatter, attention may be directed, to (2002), but it is almost impossible to ■ distinguish between the potash- and soda-felsites without a deta-ikd chemi^lexaimination. Some of the lavas are more basic than the felsites, and they will be referred to' later.oti.as .aiideiitfiSi ■ iThe felsites frequently show a streaky flow stractiire .{2701).charjictpristic of laya flows, and some have associated isith (th^.beds Qf joshes (2009) and volcanic' tufi":made, tip of v^c»tiie lapilli, (2017), brofcn jvagmenfcs of felsite (2.0J8,:27Q8,,2024)i iamd broken felspar crystals (2023) j thiSjevidence shows. that th? ,i-cicks;afe the product pf ordinary volcanoes, auA tjiat thfy'.are M Xower Silurian age, and hence Older than the granite. Some' of the ashes aiie more basic in tfiomposition (2010, 2012, 2709) ..aod suggest, that certain of the diabases and epidiorites' mfey have been lava'fl,ows>.; , .The ashes appear to be mote frequent in , Wexford, ■and somfe occUr'in Kildare. ; ' ,' ' i[ ;, . 'Pr. Hatch has exttmineji, the coariaer grdined "greenstones" of Wioklow, and divided them according to- their chief constitueattt minerals, They'are mostly whioh is welL seen:at SHeve Poye an:d Barnaveve. Dr. S. Haughton'Jias analysed ithes rock and thfr felspars isolated from it, and further researches have been' caiTied' oiit by Professor Sollas. It contains abont;-' 47 per cent. I of silica, and> has for its chief constituent a ■■lime- felspar called atiorthite (trielinic unisilicate of lime and alumina), or one beween bytownite and anorthite in, compositiou; thiS' is mixed with iron ores, hypersthene, and pyroxene which has minute lustrous plates deposited along; several of its planes so as to give it the bronzy lustre and structure of diallage. This gabbro is jDenetrated by dykes and veins oi. granophyre, a rock allied to granitite in composition, and com- posed of quartz, oi-thoolase, albite, green and black mica with magnetite, sphene, and rare zircons ; the quartz and felsp^ are intergrown together in intimate crystallographic relationship, so as to form the aggregate known as micropegmatite. The penetra- tion of the gabbra by the granophyre is of the most intimate character,! the veins being at times mere threads, and PrqfessQr Sollas is of opinion that the micropegmatite which occasioflially forms a matrix to the gabbro is due to injection of the grano- phyre on a minute scale. Further he regards the patches of gabbro immersed in the granophyre as connected by insensible gradations with the crystals of augite sometimes found in it, and he considers both to be the survival of included bits of gabbro which have escaped melting down by the heat of the intrusive rock. , These rocks are certainly later than Carboniferous time, and may even be of Tertiary age; they compare closely in structure and comppsitioh with similar rocks in the Mourne Mountains, in Skye, and in Mull. Later dykes of black basalt traverse both granophyre and' gatbro, and occasionally extend to a considerable distance iaio the bordering rocks (2122). Case B. — Phillipstown. An interesting area of volcanic rocks occurs at Phillipstown in Queen's County. These are bedded with the Carboniferous Lime- stone, and are the only instance of volcanic action of that date known in Ireland except that of Limerick, to be described 'ktfer The breccias and ashes, made up of basalt, pumiceous rack alii palagonite, but containing fragments of limestone often of'cdh- siderable size (1604, 1610), embedded in fine ash j(2081). or in crystalline calcite (1613), show that the outburst was actually of Carboniferous age. The lavas are vesicular and amygdaloidal diabases (1606, 1614), but at times are made up of Ivmbtcr^ites like those 'of Limerick,, and of compact, intensely dark basalt dASES B, Vll. & Vlil.] ■ IGNEOUS AND FOLIATED KOCKS. 39 (2733, 5)t -which has a very remarkable characteiv' lii. a, base of fclBpar'and angiterioh in brown mica are porphyritic felspars ■whioh ithemselves encloBe idioiriorphic crystsils of augite. Jll*^''® are tWb old specimens in the collection of which the exact histoity hati fceen lost,' biit which have certainly come from a, small patch S. Ev of Oorteen; One (2732) contains' relics of garnets' siuTounded by 'tings of kelyphite embeddedinia liiosaic of felspiaiVwithajniMet^ii •«vhich may possibly be idocrase; the other (3784) contaiins the-relicg of gsilfnets preserved as kelypMte,. set' in a matrix, of qiJartz gtaiiisi, BdHtdh' Strainedy and ■ containing a pitofnsion 6f crystals.of igre6i)iJal>, yellow; or ired sillimanite.' This appearfe to'-be^'a metamorphic rock, aiid ' may be a fragment Of som'6 sedimtat. enclosed in; the ijneou^'-Sbbks.'!' ■ ■'- ■■ t ."'"' '■"' ' ■ ' '■■'^"■. - ,, '• ',, Cask B.— The Carnsore Area.. This region is at present undergoing re-examination, So that it isidt possible to display an exhaitstive collection of its rocks'. It ' is occupied ' largely ' by a jslutonic complex of granitites (^raiiites without liluscovite) consisting of quartz, microcliie and drthb'clase often in lafge pifik pdrphyritic drystals, and biotite with iron-ores, apatite;' and zireoii (2079, ^0)^ The normal granitite passes mtogneisies which are well banded, much 'crii shed and crumpled (1806), and penetrated by a great Series of babic and ultrabasio dykes in ■Which hornblende is an itoportailt constituent. Many typete ' of schistose' rocks occur in the neighbourhood of the granite." ;'■!■'•' i ■ . ,-3,^ TH.E i;'OLIATED .CRYSTALLINE liOCKS OF . LEINSTER.- •0ASES; "V;il. AND VIIL— The Flanks oe the Lein^ter ',: ,.;.,,,•■ , '.Granite. ■-■ (Mips A&B; SeciSl), The metamorphism produced in the sur- rounding Lower Silurian strata by the intrusion of the enormous and highly heated mass of the Leinster granite has not received any detailed investigation.-since. ..the. work of von Lasaulx. Originally they were chieily clay rocks with coarse gritty bands, penetrated by the iptrusivQTp5ks«l|'eadj specified. The grit layers are less easily altered than those of slate (2669, 1266), and their original strapture, is observable even after ,the interbedded slates have teen converted into mica-schists. ' The slates first begin to'Sh'o'W'aBflicaceOTis glaze andfe slightly knotted structure on' the feteaVagfe surfaees even at A vtery considerable distance frofn . t)ie In^rgite of the gianite (1270,1).. The mica crystals then steadily itt'ereaSe' iffi' size,' ihdi are associated with staurolite (an orthor rhbiilbfc'Sufcailicate of alumina aE.d'iron),both minerals containing ■^a^hite'(bfex%dnai' carbon); further still the mica is interleaved •with bandsflfgranijlarquartz in' grains interlocked with oneancJtherj 40 LEINSTER AND CONNAUGHT. [CASES VII. & Vllt. and whose shape has probably no connexion with any original fragmental structure. These mica-schists are generally much crumpled (1250). Locally they become spotted, and, on tracing them towards the granite, the spots pass into crystals of andalusite (orthorhombic subsilicate of alumina), which are often of consider- able size. This is especially the case where the rock is seamed with granite dykes, as at Killiney (3178, 1248), (v. D. 21). Specimens showing the actual contact are exhibited in case A and also liere (1257). The patches of schist actually enclosed in the granite have suffered a much higher metamorphism. Amongst the minerals developed in such a case are staurolite, garnet, idocraso (teliagonal unisilicate of lime and alnmiaa) (1262, 5), zinnwaldite (an iron-lithia mica) (2670), tourmaline (1259), and; actinolite (a magnesia-lime-iron amphibole), 1252). Where the same rock has been intruded upon by basic and acid rocks, as in the neighbourhood of the amphibolite intrusion at Glendalough, an intensely crystalline mica-schist has been pro- duced (3444). While the bulk of the metamorphism is un- doubtedly attributable to the intrusion of the igneous rock, some must be due to mechanical deformation, which ha.s left its mark in many cases on the margin of the granite itself, by inducing a foliated structure on it. This is well seen about Graigue-na- managh in Carlow, where the gi'anite passes into a well-foliated gneiss (Case A, 1260). At Thomastown, where the granite is intruded into the sur- rounding rocks in a number of small masses, there occur a few singularly coarse-grained homblendic rocks, either altered by the intrusion of the granite or else, if they are the later, cooled slowly, because the granite was stUl hot during their intrusion. A great many of the igneous rocks ilanking the Leinster granite are altered from their original character, in all probability by dynamic metamorphism. Thus felsites are crushed until they resemble cleaved felspathic ashes (1218, and some placed in case A) ; ashes are strongly cleaved and secondary minerals developed, while dolerites are altered to epidiorites, and even to hornilende' schists and schalsteins. 2.— CONNAUGHT. 1. GENERAL ACCOtJNT OF THE ROCKS. Connaught is divided geologically into two very dissimilar parts by a line running from Sligo to Galway — the western tract of mountains and the eastern plain. The former is again severe^ into three regions by belts of Silurian strata ; the region extending from Benwee Head to Achill and Lough Conn, which sends out a long north-east tongue to the Ox Mountains and Slieve Gamph, i^ divided from that of Orbagh Patrick and Westport by thp. INTRODUCTORY REMARKS. 41 Carbopiferous-covered Silurian trough of Clew Bay and Clare Island, and this in turn is separated from the Connemara Moun-' tains by the trough of Lough Mask, Killary Harbour, and Mweelrea. All this ground, except where otherwise stated, is occupied by gneisses and schists, quartzites and marbles, of great antiquity, pierced and seamed by intrusive rocks of several types, from the acid granites of Blacksod Bay and Gal way to the serpen- tines and picrites of the Ox Mountains and Koundstone. The highest summits and most picturesque peaks are built of quartzites and quartz-schists, diversified by steep cut valleys and abrupt escarpments where the bedded and less metamorphosed Silurian rocks come to the surface. The coast scenery corresponds witti that inland, and the harder masses of resisting rock rear tjjem- selves against the waves in lofty cliffs, like those of Achill, which tower nearly two thousand feet above the sea. East of this line all is changed, and the broad Carboniferous Limestone plain stretches away eastwards to join that of Leinster, broken only where older rocks push up to the surface, giving rise to more rugged country at Ballaghaderin, Slieve Baun, and Slieve Aughty ; where plateaux of higher Carboniferous rocks stand above the surrounding country in the form of terraced scarps and outliers,, like those of Ben Bulben and Lough Allen ; or where the limestone of the southern margin itself takes on similar characters, and forms the terraced steps characteristic of the " Burren area." The dividing line between the mountains and the plain is marked by the western chain of great lakes. Loughs Conn, Mask,, and Corrib, continued by a belt of broad river valleys and sea gulfs, rather a significant feature when the general relations of scenery to geological structure in Connaught are carefully studied. In descending order the principal rock groups in Connaught may be thus specified : — Syatems. Series. Igneous Books. 5, Pleistocene, i. Carboniferous, 3. Old Hed Sandstone, S. Upper Sjlurie|,n, . 1. Lower Silurian, . Coal Measures, , . . .1 Millstone Grit, Toredale Series, Carboniferous Limestone, . .Lower Carboniferous Sandstone,, Foliated Bocks. Crystalline Intrusive Eocks. Intrusive and Inter- bedded Bocks, Intrusive and Inter- bedded Bocks. Intrusive and Inter- bedded Bocks. 42 CONNAtJGHT. [CASE XV. Oases ?;t".-XVli:i.-f The Foluxed Crxstalline .Socks. !'- : Although ft is by u6 means Jirpyed' that, .^e, rocks b^ it^ mounts^ifis. are th^ oldest in the; Province, yet as some', of thein present structures 'and minerfil- characters not met with' amongst unaltered . pediments, and as no definite relation'ship has as yet i)e&n conclusively established between, these Wo groups of rocks, it will be convenient tp treat them first, premising that by so dojiii^ there is no intention of prejudicing the discussion -of their ajge For convenience of desoi:iption th^ district will be split up into^ foiir areas running from north to ; south. 1, IfortJi, Mayo^ the Belmuljet and Blacksod region witti Achill Islaiid and Curraun^ ^0^1 a3;farjas Eephin,;; 2, Southern Mayo, the district of West- port' and 'Croagh Patrick ; 3, Northern Oqlway, in,cluding the 'Omey, Clifden, .and ,Leam areas^ , with the islands on , Lough Corrib ; 4, SqV/th GfiZway, ihB area from Roundstone to Gal way Town.. • , , Case Xy. — The .Ox Mountains, Belmullet and Achill. (Map C.) — The chief Plutoiiie rocks of. the Ox Mountains are coarse porpiiyritic granites (v. pa'giS , 52) at times graduating into, gneisses, which dontain all the constituents of granite biit, are foliated, A,t the western edge these rocks pass under a series of mica-schisti (2887), quartz-schists (1123), and sheared grits (the rock called " pennystone "' in this area) (874) like those occurring in Donegal. This series, which in the nA,ture and association of its potnpon!ent rocks presents every reason for supposing it to be of sedimeiitary origin, sweeps across Mayo . froni Nephin to Belmullet, its coiistitiient membets being several times repeated by folds, the quartzites (2999) and quartz-schists forming mountainous country, thg. 'mica schists and lead-coloured phyllites forming rolling up- lands. The limestones are gritty, full of iragmentaL quartz, and fQliajced.„with.iay.ers.of ^jaerald-grfien_mica (303.3), ...Theseu. rocks coBfie into contact with gneisses (1128, 1132, 2962) an4 granites about Belmtdlet, their contact with the latter being clearly due to intrusion of the granite, which has produced, along the junction planes, w knotted schist (1146, 1134 and 5) with "«ye6 " of 'felspar surrounded by folia of mjca.. The junction with the gneisses is \isually a thrust plane (3018), and the gneisses are massive (1126), hornblendic or actinolitic (1130), micaceous (1135), granulitic, much contorted (1128), a'nd 'penetrated by dykes' of amphibolitti (1145, 1129), epidiorite (1138) and recent basalt. A dne grained, slabby, quartz-schist, Yevj like that known as " moyne-schist " in the _Scottish ' Highlands, is found to the east of Erris Head Following the sedimentary series down to' Achill Island the ciieFfeatures ai-e the abundance of quartzites (1150) and quartz- schists {1151J pas&ing into massive quartzose conglomerates ,(lli8) which have been much crushed by earth-movement so that the pebbles -have been sometimes drawn out to thveads-ni49).. - CASE8 XV.-XVIII.] FOLIATED CRYSTALLINE EOCKS. 43t- Case XV.— Croagh Patrick and S. Mayo (Map C. and D.j Sec. 3bj.' A bell (ji Tniea-schists, coarse, foliated, -pehhlj, gritSy sstid' ijra2}hitic schists, flanks the Croagli Patrick range to the north ailfi) passes to Westport to join the similar rocks of the Ox Mountain area. §itarf^M!«s.,ooou]; on Oroagh Patrick, , an^ tq , the^ north there is a great mass oi serpentine (1153, 4, 5) probably produced by the metamorphism of an -igneous rock. Knotted schists ^ith all the characters produced by contaot-metamorphism occur in the neighbourhood of the Corvockbrack granite. Cases XV., Xyi., and XVII.— Northern Oalway (Map D.) This a,rea ipcludps the interesting ground between Oqiey and Clifden, that about Learn, and the Islands on Lough Con-ib. The rocks chiefly represented are jfM*sco'uiie-(1157), chiastol%te-{\.\^^\ and , ioZo- schists (2513), limestones (1169) and dolomites (1170), incliuJLng the beautifq.1 marbles of Gregg quarries (655, 6). These would be mope valuable if only they could be raised }.n larger bjpcks. Copper ores have been found in this neighbourhood. A^s^ci^t^cl ■with the limestones are ophicalcites and serpentines (ll61, 4, 5, 6, 7, 1182, 3, &C.) from Streamsto'wn, Kecess, and elsewhere, wljich form the beautiful Galway marbles and " Eozoonal rook " (11^2), so called from its resemblance to the Canadian rock whic)i was o^co supposed to contain the earliest known fossils. These rocks consist of fine or coarse puckered bands of a light green serpentine alternating with layers of crystalline calcite. Some of the darker and more massive serpentines which have the characte,r§ found in those derived from igneous rocks, are translucent and very beautiful (1181). These serpentines, ophicalcites, ei,ud, marbles, are most useful for internal work, as is admirably, shown in the Museum of Science and Art, the National Library,, and many public buildings in Dublin. About Learn the rocks ,^re chiefly knotted schists, some of which are probably produced by contact alteration (2923), others are of the foliated grit type (6§7). Associated with , these , are lead-coloured mica-schists (2910)^ phyllites often much, puckered (2924), and liornblende-scJiiks^ probably in, most, cases produced by , the metamorphism of basi? dykes (1178, 2563). There are garnet rocks (887), quavtzitesi.{7^'2), with foliated and crystalline limestones (G57,, 8). Gneisses ?i.lsn occur (2541), but some of these are .certainly. folj,a,ted graiji^es. Siinilar ^meisses (1184, 5) and schists. (ll§7, 97) occur on Lqugji Corrib , and its, islands, associated , with tl^^ serpentines. {ll^Sf'&Q, 92) to be subsequently described {v. page 55). Case XVIIJ.— So\;tliem Galway. This area extends east\v-ards from R'oiindsto'ne to Galwity. " Aboilt Eoundstoiieand Slyrie'Head in south-west Galway mica-g'heisses (120()y occur associated' witli h&rnhlendic gneiss (1173), epidote rock, a rock' mainly mad^ .ilp of epidote (an unisUicate of lime, iron, arid alumina), (117-5),' aiid " moyne-scjiist " (1158), all being penetrated by the igneous focks to be mehtioiled later on (■;;. page 53). At Town Park oti S.E.' Galway, the pliitonic complex ijifclades many foliated 'rocks, but 44 CONNAUGHT, [CASES XI. & XII. very f&w which can be safely referred to a sedimentary origin. The massive foliated rocks will be described in connexion with their igneous accompaniments {v. page 53). Cases XI. and XII— The Silurian System. The rocks of this System come to the surface in three very im- portant areas ; at Ballaghaderin, the environs of Clew Bay, and between Mweelrea and Lough Mask, besides other and less impor- tant regions like that of Slieve Baun and Slieve Aughty about Loiighrea. The rocks do not present any great differences from those already described in Leinster, but the local peculiarities will be noted below. Lower and Upper Silurian rocks appear to occur in the same areas, bvit the lowest rocks of the system are not known there, a significant fact when taken in connexion with the absence of all Cambrian rocks. A remarkable feature is the presence of contemporaneous volcanic rocks in the Upper Silurian System, a thing not known in Britain, and only paralleled by the igneous rocks of Clogher Head in Kerry. Another impor- tant point is that some of the Silurian rocks are so intimately asso- ciated with ciystalline schists that it is not easy to draw a boundary line between them, and this has led to the belief, which may possibly be correct, that the sediments have passed into foliated crystalline rocks under the influence of metamorphism. The rocksareof little economic importance, but haematite has been worked at Lough Gowna and Drumsna, while anthracite in nearly vertical beds occurs at Kilnaleck, and lead and other veinstones exist in the Silurian and Carboniferous rocks near Lough Mask. Some of the most striking scenery in Galway and Mayo, as at KUlary Harbour, Mweelrea, and Delphi, is situated in these rocks. The fossils will be noted under the localities in which they have been found (v. page 112). In the district of Uggool and Ballaghaderin two divisions of the Upper Silurian rocks are represented on the published Survey maps; the lower, containing fossils attributed to Upper Llandovery time, consists of red and purple sandy shales (926) with sandstones and grits; the tipper, or Wenlock rocks, are deep purple ;?a^s with a few shale beds, and a band of concretionary limestone. Associated with the upper division is a series of volcanic rocks, jncludin" columnar and other felsites and their associated breccias and ashes, with intrusive masses of augitic granophyre and diabase dykes (v. page 51). About Mohill, Drumod, and Ardglass the Silurian strata . con- sist of dark greywacke grrii with bands of slate (1440) like that found in the Slieve Baun area to the south-west ; the few fossils found near Slieve Baun indicate that Llandeilo, or Bala, or even possibly both Series are present. Patches of Silurian rocks, slates (859, 860), a,ny\ grits (1119) occur at Louisburg, west of Croagh Patrick, and on Clare Island (695), where an Upper and a Lower division have been separated CJA8ES tt. & XII.] SILURIAN HOCKS. 4S and mapped. Fossils are found in the calcareous shales di this area (928), and some of the slates and grits have the aspect of such alteration as is produced by the intrusion of igneous rocks. The Mweelrea and Slieve Partry area (Map D; Sec. 30). Mr. Kinahan has divided the Silurian rocks into the following sub- divisions, in descending order, and he suggests the annexed corre- lation with English equivalents : — 4. Salrock Beds, = Ludlow Series. 3. Mweelrea Beds, = Wenlock Series. 2. Owenduffor Gowlaun Series, = Llandovery Series. 1. Doolough Beds, = Lower Silurian System. , The Doolough Beds consist of olive green slmles and slates (1120) alternating with thin greenish grits (696), and sandstones, sometimes pebbly (646). Many fossils have been found in these beds, and are referred to on page 112. The Owenduif or Gow- laun Series consists of conglomerates (1003), grits (647, 8, 9), slates, shales (929), and quartzite (869), with a bed of lime- stone, and at certain horizons beds of iatersti'atified (?) felsitic lava. The Mweelrea Beds are coarse green and purple grits with interbedded massive conglomerates and olive green slate bands, associated with intrusive felsites near Killary Harbour, and lavas of felsitic and andesitic composition about Lough Nafooey. The Salrock Series is made up of green slates (923, 4) and thin-bedded grits, occasionally fossiliferous, covered by red slates, thick quartzose grits, and limestones (875). A large series of fos.sils has been obtained from the Upper Silurian strata, including characteristic Corals, Trilobites, Brachiopods, Gastropods, and Cephalopods. As the Geological Survey is at work upon this district it is possible that the classification and correlation given above will need modification ; at present it is safe to state that the quartzite of Lough Nahaltora, which is identical with that of Croagh Patrick, both containing a thick boulder deposit, appears to underlie the Doolough Beds, and is in turn apparently underlain by indurated fos.". The long strip which extends from Lough Allen to Ballagh- 3,de^U contains some remarkable rocks, which are paitly volcanic i^ii! origin. A,hout Boyje and the Curlew ifills they' are brpkeri ii,p ..by extremely sharp rectangular joints, and consist' of very corapaci grits (-2470, 3) and breccias (2471, 2) almost exchisively compps'ed pf srnall and large fragments of felsite, and probably lii^de out of volcanic material ejected into ^ater a,iid theii com- pfl.cted into i-bck ; pebbles of slate, schist, jasper, aild vein-quartss are, however,,.tp be found sparingly in this rock. ' .Old Bed Sandstone rocks cover , a considerable, area nprth of Westport and west of Castlebar (Map C and D). They consist almost exclusively of con-gloimrates, thp^ " ,Croaghmoyle conglome- ;X"ate," made-up of f ragmen,tS: of granite, san(fel;one,,and quai-tzite, with xare seams of sandstone. They are estimated to be frpm 700 to 1,000 feet in thickness, and they give i-ise to a rugged country ..with lofty conglomerate cliffs. The rofeks mapped as Old Red Sandstone about Slie'Ve Baua 'consist <)f siliceous grits and sortrfstoncs (723), passing into sub- ■ angular conglomerate (1441), which contains, large well-rounded 'pebbles of Silurian grit and smaller subangular pieces of the same 'material. Lumpy masses of siliceous rock ^(a kind of jasper, ' 651) occur here at the base of th© Series and- fill up hollows of denudation in the surface of the SUurian rooks. .' • ■< : ' . The LoUiihrea and Slieve Aughty area has banded irown and 'chpcblate .coloured sandstone (1632), interbedded , with pnrple micaceous sandy shale (1635), quartzose conghmeratf wi^h fragmehfakl felspar and epidote (1640), and occasional seams of '' cornstonej" an impure earthy and ironstained limestone. . pASE XIII.] CARBONIFEROUS, ROCKS. 47.- Case .XIII.— The. CARBONirERO US SrsxEM. ..'.ri!. Thfe'. divisions of this System that occur in Lein'ster •q.re- ail^' to' be! recognised in Connaught. The friigineiltal basement beds, howQver^ are jnore widespread and better developed, while the liniesij'ones are oh the whole purer. In some parts, indeed, the whole of the Carboniferous Limestone, Series must be treated a^ one, for such lithol6gical divisions as do occur cannot be, traced far, and until rec9gmsable gones of fossils are established, it is hopeless to, attempt to establish a tripartite classification over the etitiire area J (or tlli^ reason nodivisiohs ha^Ve been, hitherto establiipe'sJ in the iniddle of the Province, or else the tiiinestohe ha^ been jtll' relegated to the lowest Stage. The higher Carboniferous "rockV are only to be. found .at the .JS^orthreast, where-tbe presence of ^he hugp ouijiiers of Lough AUen indicates tje former great extension of l^ose bedsto.the, west, and the .enormous amoiint of 'material W|lfichiTOu.st hayp %?4 removed by denudiition in the interval bet\vepn thepavboniferous ,Period and the present, 4i; interval during ■whicLthis part of Ireland has probably been above Y^^^j? and ,ex,posed to the action of rain and- streanis. The thickness|jOf the rocks, of this System at its ruaximura development appears to be between 5,0Q0. and 6,000 fee^, but ^ t}ie , different beds attain, their fliaxima at different places .this thickniess would never be met with, at one spot. . ;, . ■As, in Leinster the limesfjone rocl^s yield black marbles near Ga,lvray and splendid building material, durable and .capa,ble of deliqate workmanship, in Qalway, Mayo, tlie Arran Islau^s, and elsewhere. The sandstones of the Yoredale and Millstone Grit Sei;j^s yield freestones, sometimes glazed along the joints with quartz so a,s to be extremely durable; flagstones and the thin, sm,6oth,; laminated, flag used for roofing, and: known as "Du'nhioi-d plate," are also: obtained from these rooks. . ■ ^ ^"' Lower Carboniferous Sandstone (Sec. 30).; — Owing to its low t^p and its considerable thickness this .sub-division cpvfJrs'a lii-ge afea in Mayo to the west of KillalaBay^, arid it crops ouii froiu: undeip the edge of the Carboniferoiis Limestone whenever that Series abuts on jnore anciejat rocks in the northern part of 'the Province. It becomes thinner *hen traced Southward, doilbtless owing to, the w^ie extoijit ' of the deep CarboniferQus sea Over tl^e rocks, of Connemara, but it begins to assume niore importance on th^ borders of the Slieve Atighty range, when it takes on the character^ of the Lower Limestone Shale of south- w6st Ireland. In the Killala Region the total thickness of strata is about 1,060 feet and the rocks roll in gfehtle curves, here arid therte broken by ,^!]lts,a^d,pen,elTated,by,opje or two large intriisiye, dykes of doleyite (■«. p. , 51) ; they are red,^ brown, yellow, and estrjthy .tfirtdstqnes, darkbrqwD shales, calcareous sandstonesffOl),.a,nd^c)m'eF itjmes thj,n .b^n,ds opjicqncretionary r^odviles of ^ime^ton^. The 1^3,54 bo)r4ering the east of, Slievei Gamph appears to bo only J,50 ,feet ,|ihick, and is based on a quartzose conc/lomerate followed by pvirple 43 ^oNNAyoftf. [case xiii; sandston4 and Calcareous grits (699, 700) containing a few traces of fossils. The rocks maintain pretty much the same character when they reappear to the north-east about Ballaghaderin and Boyle, except that a basal breccia derived from' the denudation of the Old Red volcanic rocks occurs here (2474) ; the few inliers, mostly of conglomerates, grits (1434, 6), calcareous sandstones (1433, 8), and micaceous flagstones which appear from beneath the great Limestone Plain are now regarded as the Carboniferous basement, and not as Old Red Sandstone. Bounding the north side of Slieve Aughty come about 150 feet of shales with shells (1631), shaly limestones (1646), and occasionally grits, flags, and sand- stones. The Lower Carboniferous Limestone. — South of Killala Bay the Limestone Series begins with a bed of oolite about 80 feet thick (861), in which elongated crystals of quartz occur ; this is followed by a fine crystalline limestone (705, 6) banded with shales and altogether not less than 600 feet in thickness. In the neighbourhood of Skreen the limestone has been much crushed and specimens show " slickensided " surfaces (856, 7). In the great Limestone tract east of Sligo Bay the lowest division is feebly developed as a band of magnesian limestone about 100 feet in thickness, showing occasional pebbly bands at the base when it comes into contact with the imderlying crystalline rocks ; but to the south-east it is more important and yields good building and even ornamental stone. About Boyle and Carrick-on-Shannon, there are light steel-grey to dark-grey limestones with occasional beds of shale and bands or nodules of chert. Over the western part of the great central plain the limestone is grey, pure, and fossiliferous, massive or flaggy, with beds of grit at the base, but not divisible into separate series, although it has been possible to roughly relegate certain portions of the Series to a lower stage, and others near Eoscommon to the middle division- The Lower and Upper Limestones of the Slieve Aughty range are very pure and free from sedimentary ingredients, though they contain some beds of chert. They are crinoidal (1622) often dark and shelly, (1644) and sometimes seamed by dyke-like plates or masses which have the composition of dolomite. The alteration of these portions is almost certainly due to magnesian water per- colating into the mass of the rock from the walls of the joints by which the rock is ti-aversed. The Lower Limestone is about 2,000 feet thick, and although it is thinner towards the east, bands of shale and sandstone make their appearance in that direction, especially in the central part of the Stage. The Middle Carboniferous Limestone.— For reasons already stated this division requires separate description only at a few places. East of Sligo Bay there is a lower sandstone division 500- 800 feet thick towards the north, followed by calp shales, and limestone, frequently fossiliferous, with masses of corals, and cheit bands amounting to 700-^1, OOOfeetin thickness ; landslips are of fre- CASES Xni. & XIV.] ' CARi30NIFlER0tJg HOCKS. 49 quent occurrence in tliese rocks. Argentiferous galean and blonde liavebeen worked at Abbey town in veins in the Middle Limestone. About Castlebar (Map C) the Lower Limesftone seems to be absent and the lowest rock «een is a division which corresponds to the Calp, and near Lou^hrea. the Middle Limestone is dark in colour and ciinoidal (1628) ; it contains chert bands (1627). A good idea of the bedding of the limestone is given by the photographs (P. 81, 92) of Aughros liead in Sligo. The Upper Carboniferous Limestone.— -A fine, grey, crystalline, limestone succeeds the Calp to the east of Sligo Bay and forms the great plateaii on the summit of Ben Bulben and the other outlying " buttes " or hills about Sligo. It is 700 to 1,000 feet thick and is much traversed by joints. The streams and springs penetrating along these fissures have dissolved out lines of ravines and caves which follow the direction , of the dominant joint systems. Near liOugh Allen and Lough Arrow the limestone is penetrated by pot l}oles and swallow holes resulting from the same cause, into which rivers and streams plunge and flow .underground as they do in the Ingleborough region in Yorkshire, and many other lime- stone tracts. Towards the south this division thins down to 300 or 400 feet. A very peculiar structure is noticeable in the lime- stone at Ballymore in Koscommon, where the strata are traversed by vertical planes like slickensides which, however, do not in any way break the continuity of the limestone beds as they would do if they resulted from faulting in the ordinary sense (653). The Upper Limestone of Loughrea and that of the Aran Islands is so exactly of the Burren type — to be described under the Province of Munster — that it is needless to do more than refer to it here. The Yoredale Series. — The great outlier of the Lackagh Hills and Lough Allen is ba,sed on masses of sandstmie and grit which often give an excellent building stone. They are evenly bedded and about 300 or 400 feet thick, and are succeeded by 500 feet or so of fossiliferous black shales with a little worthless coal and bands of ironstone (930, 932) of which the best known were at one time largely worked at Creevalea and Arigna. The thickest ironstone is a continuous band varying from 6 to 10 inches in thickness, and containing about 40 per cent, of metallic iron. The Millstone Grit Series. — In the Connaught Coalfield this series consists of massive, white, exceedingly hard, quartzose, grits, and flagstones, quarried near Lough Doo, with fine conglomerate capping the higher hills of Lough Allen, and forming the great scarp of Slieve-an-Ierin. There are two seams of coal, the lower called the "Crow Coal" from 2^ to 4 feet thick is valueless because it is full of shale and other impurities, but the upper, 60 feet above it, called the "Middle Coal," though only from 1 foot to 2 feet 6 inches thick, has been much, and profitably, worked in the three districts into which the field is divided by denudation, the N.W. district, that of Arigna, and that of Slieve-an-Ierin. The 50 CONNAUGHT. [casts, XIV, Mil.lstone grit appears to ,be about- 150 feet tliiuk, and there ar? generally seams of ijiXTpvixe fireclay associated -with, the Crow Coal. The coals cpntajn fij'oni 7 to 20 per cent, of ash. !f he Lower Coal Measuifes.— rTheSe contain marine fossils in the Colina,t(ght field and are made ujp of lOO feet of dark brown and black fissile «toZeg passiug towards the south into flagstones and grits with one Seain of cnal, the " Top" or "Third Seam," which is 1 foot 8 inches thick in the iiorth-we^t districlt, but of ]ittl6 value, , , . ,. ■ ' , ■ • • . - ': • - ' Case XIV.^The Pleistocene System. The Lower Boulder Clay.— This deposit is much like that alreaidy' described from Leinster. It occurs in similar drumlins which are parallel -to the ice striae in direction, and are made up of clay 'eontaining chiefly blocks of local rocks and sometimes blocks of exceptional character;' like the gypsum fragments found near L. Allen (707). Occasionally shells and shell fragments are found in itj and it is at times stratified. The earlier direction of movement 'appears to have been outwards-from the great snow shed already described — that is to say, radiating out from a point near Ballinrobe ; but later in the period, Scotch ice seems to have overpowered the local ice, and the movement north of the snow shed was roughly from N.E. to S.W. Specimen 1122 is a portion of the rock under the Boulder Clay of Mutton Island in Galway Bay, to illustra,te the striation of the rock over which glaciers have moved. The Middle Sands and Gravels correspond with those occurring in Leinst«r and are frequently present, and iihe Upper Boulder clay and. local moraines of the Connemara Mountains call for no further remark. Eskers are frequently present; sometimes they are of great size, and erratic blocks occur On them. Terraces of deposit or denudation are to be found high up on the flanks of some mountain ranges ; thus Mr. Kinahan describes mountain terraces between 60 and, 200 feet above sea level in the neighbourhood of Killary Harbour, and others between 300 and 1,200 feet high about Lough Graney. The.P^t Bogs are, either mountain or valley bogs ;, those of the latter type , often occur in the hollows between drumlins and ,are , sometime? , more th^n 30 ,feet in flepth. Varieties pf peat have been distilled for gas-ma,king,^as at Daranmona in Galway, . (677). Shell uiarls are of frequent occurrence under the peat, and Jog'^rprij fQre used at one time to be a valuable commercial pro- .duct ; it is now, hovt^ever, very rarely excavated. Thfi calcareous springs in limest.one districts sometimes, form considerable 4?po*>i'-s of tufaj^ which is either deposited alone or ag a cement for gravels and san4. , ; ■ , .CASE C] iGNfeOtTS ROCKS. '51 2. THE IGNEOUS ROCKS OP CONNAUGHT. It is only possible to arrange the igneous rocks of Connauglit on a geographical basis. The following areas are dealt -with separately:^ — 1. Killcda and Castlehar ; 2. The Curleiv Hills, in Rosoommon ; 3. The Ballagliaderin area ; 4. North-west Mayo ; 5. The Ox MovrntaiTis and Slieve Gwmph ; 6. South Mayo ; 7. North-west Galway ; 8. South Galwq,y, including the areas of Leam, Lough Corrib, Roundstone, and Galway. CASE C. — KiLLALA AND CaSTLEBAR. (Map C.) — ^On the west side of Killala Bay the Lower Carboni- ferous Sandstone is penetrated by dykes of coarse-grained dolerite or gabbro (2481), an tfphitic rock, consisting of labradorite and augite, with some biotite, iron ores, and a little hornblende and olivine j the constituent minerals sometimes have a parallel arrangement (1883). The rock may possibly be of Tertiary age. In the neighbourhood of Castlebar somewhat similar but less coarse- grained rocks are to be found ; they are intrusive into the Car- boniferous rocks or the older masses in close proximity. These are fine or coarse-grained olivine-dolerites (2482, 3). Case C. — The Curlew Hills. In the Curlew Hills, about Boyle and Lough Key, volcanic tuffs, probably laid down in water, occur (2472, 3). The constituent frag- ments are chie&y porphyrites and trachytic_/«Zsi I. Lower Basalts J Intrusive and Inter- bedded Bocks. 8. Cretaceous, . fChalk, ■ (.Upper Greensand 7. Jurassic, Lias, ... ... 6. Triassio, Keuper, . . ... .Bunter, . .... 5. Permian, . . — 'Coal Measures, .... Millstone Grit, .... Intrusive Eocksj - i. Carboniferous, . ^ Toredale Series, .... Carboniferous Limestone, . (.Lower Carboniferous Rocks, 3. Old Bed Sandstone, . 2. Upper Silurian, . ( Tarannon Series l {.Llandovery Series, . .3 Intrusive and Inter- bedded Roots. .Intrusive Rocks ? 1. Lower Silurian, , ( Bala Series, "t I Llandeilo Series ) Intrusive Rocks. Foliated Crystalline Rooks. — Intrusive and Inter- beddod Rocks, Cases XXIII.-XXVI, I., II., and XXXII,_Foluted Crystallink Rocks. As before, it will be well to describe first the foliated rocks of the Mountains, merely for convenience and not by any means as an indication that they are necessarily the oldest rocks in the Province. After them some rocks metamorphosed by the influence of igneous intrusions, such as those of Antrim and County Down, will be described. The rocks will be treated in the following divisions : — 1. The area of North-east Antrim ; 2. Donegal, Nortli-. west of the Bamesbeg granite ; 3. Donegal, Soutli-east of the same granite ; 4. The area from Moville to Raphoe ; 5. The Derry region ; 6. The area of Pettigo ; 7. That of Tyrone ; 8. Product^ of contact-metamorphism. ' .CASES XXIII. & XXIV,] FOLIATED CRYSTALLINE ROCKS. 57 Case XXIII.— The Antrim area (Map F; Sec. 2; P, 63, 74). This small district of foliated rocks extends from Murlough Bay to Slieve-a-norra, but as the only rocks in contact with them are not older than the Old Red Sandstone and Carboniferous Systems, the only guides to their age are lithological characters and a comparison with the rocks on the opposite shores of Argyllshire, neither of which can receive implicit reliance. The chief rocks are schists or gneisses, which may be altered grits, consisting of rounded crystals of felspar or quartz grains with foliation planes of mica (820, 2), extremely dense cMorite-schists (1047), and very coarse, black, crystalline limestones (605, 7), sometimes penetrated by red felspathic veins (608), and resembling the limestones which occur in a line with them in the Mull of Cantire and in Derry to be presently alluded to. There are also foliated igneous rocks including epidiorites in this area (v. P. 74). Case XXIII. — Area North- West of the Bamesbeg Granite (Map E, Sec. 26; P. 55, 78, 91, 82, 88). The rocks here are often merely altered sediments such as quartzites (967), which sometimes show those linear structures, due to stretching and folding, which Mr. Kinahan has aptly termed " muUion structure " (1059) ; theso are sometimes micaceous (1061), and pass over into quartz-schist (1062); they are interbedded with slates (1067), actinolite and horn- hX&nA&schists and phylliies, which often contain staurolite (1049) and andalusite (823), crystalline limestones either pure and com- pact (965) or else dolomitic (963), and containing crystals of garnet (584), actinolite (970), mica (962), tremolite and idocrase (584). These minerals are developed where the limestone occurs in junc- tion with, or enclosed in, the granite, and where it has been highly metamorphosed A remarkable rook called by Mr. Scott " spliene rock" occurs at Annagarry, and in the granite near the limestone of Barnesbeg Gap ; it contains orthoclase, green pyroxene, sphene, apatite, and sometimes scapolite. Sterry Hunt compared this sphene rock to that associated with the Laiirentian limestones in Canada, and his description appears to indicate that the rock occurs at the junction of the limestones with the gneiss. In the schist patches enclosed in granite sillimanite, andalusite, and kyanite are developed. One of the most interesting bands in this series of rocks is a great boulder-hed (689, 691, 2) extending for many miles and containing fragments of granite (1053, 4), and other rocks in a matrix consisting of crystallized minerals. The quartzite of Muckish is felspathic, and decomposes into a loose quartz sand, once much used for glass making in consequence of its extreme purity. Fine grained gneisses, possibly modified granites, occur at Bloody Foreland (1048). Cases XXIII. and XXIV. — Area east of the Bamesbeg Granite (Map E ; Sec. 26). A set of rocks somewhat similar to those last described stretches ever a wide range of country from Malin Head to Donegal Bay ; it is even possible that they may be the same rocks repeated by a fold. The gneisses are for the most part ,58 ULSTER. [CASES XXIII. & XXV. jbliated granites (1050, 2801, 3). The mica-schists aregeneiially muct crumpled (936), the larger folcls being crossed by a minute puckering almost at right angles to their, direction (1069), and sometimes an appearance of a double foliation is to be. seen (lft94). The intensely indurated shales of Tintown have yielded pyritous markings which are like the relics of Graptolite3,,a point which, if satisfactorily established, would give precise information as to, the age of the bands in which they 6cc\ir, and possibly of the entire series of foliated rooks (v. case 1, and page 10.9). ■ Other slates contain chiastolite (1070), aiid- andalusite (2792), while Schists, composed chiefly of kyanite and sillimanite are not uncom- mon near the granite masses. These minerals, together vrithi the structure of the knotted schists (1071), show the important influi ence in this area of contact metamorphism of a type similar to that produced by the contact of plutonic rocks. Quartz-schists (1077), the boulder-bed aXreadj descAhed (691, 2), limestones with garnets (957) idocrase, sphene (956), and a green mineral probably diopside or some other form of pyroxene {958), saccharoidal marble (953), pebbly (819) and sheared (592) limestones, ophicalcites (1074), dolomites (591), anthophyllite 1 rock (1898), and soapstohe (1075) are amoiigst the principal constituents of this remarkable series. The white marbles are capable of an excellent polish, and can sometimes be raised in large blocks ; the soapstone and its allied " cam-stone " have been quarried for lubricating purposes. Similar rooks extend to the Barnesmore granite area (1460, 5), and about Castlederg there are crystalline (1587), dolomitic (1582), and micaceous lime- stones (943) penetrated by epidiorites and hornblende schists. The crystalline limestones of Culdaff are of importance fi'om the fact that they contain radiating masses of calcite which have been considered by Professor Hull and others to be Corals. They, however, do not present any absolutely indisputable evidences of organic origin, and are not more like Corals than many of the purely inorganic concretions which crowd the Magnesian Lime- stone of Durham. Several specimens of these supposed corals will be found amongst other doubtful fossils in case 1. More recently, Professor SoUas has detected bodies which may possibly be the remains of Radiolaria in the same limestone {v. page 109). Some of the photographs (P. 78, 82, 85, 86, 87, 88) represent cliffs formed of the different foliated rocks of Donegal. Case XXV. — Area of Moville and Raphoe. This area is really an integral part of that last described. In it are found friUed •phytlites (1086), chloritic schists (1085), workable slates, still showing the bedding planes crossed by those of cleavage (1092, 3) and some in, which the cleavage planes have been contortpd (1087), quarizites (1084), quartz-schists (1081), grits (IQSS), coarse .grits or fine conglomerates with rounded and crushed fragments of quartz and felspar in a schistose matrix (947, 9), and dark-coloured crystalline limestones (941). CASES I., II., XXV., FOLIATED CRYSTALLINE ROCKS. 59. XXVL, XXXII.] Cases XXV. and XX VI. - Londonderry Area (P. 85, 86, 8f). Much of this county^is formed oimica- (1112), quartz- (1114), and' cMorite-schists (1400) with sheaxed grits (2813), like those of ' St.: Johnstown and Raphoe. About Dungiven there are extremely' coarse, black, crystalline, limestones (1389), which continue the line of similar rocks from Oantire to Murlough Bay. The little area of Omagh, divided from the last by a Carboniferous . outlier, contains similar schistose grits (1539), graphitic schists- (1541), and, near the town of Omagh, a curious set of talcose rocks which may possibly be metamorphosed igneous products (1550). Cases I. and II. — The Area of Pettigo. For want of space at present the foliated rocks from this region have been placed witji other recent acquisitions in oases I. and IT. They ai;© now delineated on the Survey maps as of Archaean age, the evidence being partly their lithological character which links them with the " old gneiss " of the north-west Highlands of Scot-) land, and partly their position below schistose rocks of the S^^V mentary types already described. It may be pointed out, jn passing, that these schistose rocks extend unbroken over the country to .Derry, where they come within a few miles of the unaltered rocks of Pomeroy and Desertcreat. These unaltered rocks contain Lower Silurian trilobites like Ogygia, Trinucleus, &c., which have been identified and figured by Portlock. Such contiguity would seem to indicate that the schistose series are likely to be at least older than the Llandeilo rocks, a conclusion which must inevitably push back to Pre-Carabrian time the age of any rocks deposited before them, and separated from them by an unconformity. The Pettigo rocks are coarse hornblendic gneisses (516), contorted granulitic gneisses (520, 4), often full of garnets (518) and occa- sionally showing adventitious minerals like molybdenite (1103), felspathic eclogites which contain garnets and green pyroxenes with a certain amount of felspar (522), garnetiferous amphiboliie (534, 560), and schists and gneisses containing three or more of the following minerals — felspar, quartz, hornblende, biotite, mus- covite (523, 7, 531). These are penetrated by diorites, epidio- rites (517, 1109), and pegmatites (1105, 8), the latter being the source of the kaolin used in the mamrfacture of the finer sorts of porcelain made at Belleek. On their northern boundary these rocks, which have all the characters of a foliated plutonic com- plex, are covered by flaser-schists containing leriticles of quattz which may once have been pebbles (561), phyllites (566), and pebbly schists (572). Case XXXII. — The Tyrone Area. A two-fold series similar to this occurs also in Tyrone, but the plutonic and foliated rocks are rather more varied and contain breccias and what seem toibe other volcanic products. The foliated rocks are placed in case XXXII. devoted to recent acquisitions, and include gneisses (1117), breccias (1527), said silvery mica-schists (1523), containing garnet (1517), hoi-nblejide (1516), and andalusite (1520).j 60 ULSTER. [CASES XXVI. & XIX. Case XXVI. — Products of Contact Metamorphism (Map F). The rocks altered and crystallized by the undoubted action of intrusive masses of igneous rooks are placed in sequence with the foliated rocks in case XXVI. The intrusive dolerites of Antrim show the effect of contact-action on all types of sediments. Sand- stones are indurated (971), Carboniferous a-nd Liassic clays baked into porcellanite (636, 624) and lydite (831), and Chalk converted into crystalline limestone (628), (D. 28). This marble is an ex- tremely interesting roukj and is as coarsely and thoroughly crystal- line as most ancient marbles, although no minerals other than calcite appear to have been developed (972, 6, 9). The flints are converted into a red jasper- like rock, whether actually enclosed in the basalt (637), or in the flint gravel which has been intruded upon by the rhyolite (977). The basalt intrusion to the south of Ballyshannonhas hardened and altered the Yoredale shales andsand- stones which surround it (1504). The intrusive granite mass of Crossdoney has altered the grits, sandstones, and shales which border it into purple lydite (1559), hornfels (1571), and mica rocks, consisting of granulitic quartz, associated with numerous flakes of a rich, warm-brown mica ; it has not however generally produced any marked foliation, nor even in all cases destroyed tlie bedding planes ; however, no other original fragmental structure can be now detected in the microscopic sections nf the rocks. Contact alteration also occurs round the other great igneous masses in Ulster, especially the granites, but these instances have not yet been studied or described in any detail. The Mourne granite has merely baked and hardened the rocks which surround it without effecting any great mineral change. On the other hand the Newry granite has produced an aureole of metamorphism extending from half to three-quarters of a mile from its boundary. Mica is first developed, then it becomes more plentiful aiid larger, until the rock passes into a mica-schist, whose junction with the granite is quite sharp. Case XIX — The Silueian System. (Sec. 1, P. 82). — The rocks of this system are found in a broad band sweeping frcm the coast of Down through Monaghan into Cavan (P. 70). This region is practically an extension of the Southern Uplands of Scotland, with which it agrees in its com- plicated structure of close packed anticlinals, and in the general nature of the rocks. The anticlines display Bala and even IJandeilo rocks, the synclines are filled with the more recent deposits of the Upper Silurian System. Towards' the north the sedimentary rocks are penetrated by numerous dykes of diabase and mica trap, and consist of grey, purplish and greenish grey grits, often micaceous, with flagstones, conglomerates, and some slates and bands of dark graptolitic shales at several different horizons. Mr. Swanston and Professor Lapworth by the examination of these organisms on Belfast Lough and the shores to the east have been dAsi! XIX.] SILUfilAN ROOKS. 61 able to establish subdivisions of the graptolite bettrmg stales. Messrs. Clark and Peach have traced four divisions as far as Hillsborough and the three lower divisions into County Armagh. They have also detected the fifth and highest zone noted below. These divisions are given in descending order : — 5. Beds 6 miles iV. of TievesMlly, 1 4. BlachShales and Flags of Tieve- >■ =Taraunon Series. shilly {Exiguus zone). J 3. Coalpit Bay Beds {oj Lap- I = Llandovery Series. worth). J "^ 2. Black Shale of Camalea and \ barren Sandstone of Coalpit > = Bala Series. Bay. ) 1. Shales of Bally grot and Craig- \ = Lower Bala and Llan- avad. y deilo Series. The Ballygrot Beds contain Leptograptus, Coenograptus, Dicel- lograptus, Didymograptus ; the Carnalea shales, Climacograptus, Diplograptus, Lasiograptus ; the Coalpit Bay Beds Rastrites, Monograptus gregarius, Diplograptus acuminatus, D. vesiaulosus, Cep)halograptus cometa, and Retiolites ; while the Tieveshilly Series has yielded Retiolites and several characteristic species of Mono- graptus. The rocks are much contorted, crushed, and cleaved, and it has been noticed that the cleavage makes a higher angle with the bedding in coai'se than in fine grained bands. As is not unusual, the black shales have been supposed to contain coal seams, and numerous shafts have been sunk into them in the vain hope of winning coal. The rocks do not vary much in character when traced to the south west as far as Cavan, but beds oi conglomerate from eight to fifteen feet thick become an important factor in the series (one of these, that of Granard, has been already described under Leinster, v. page 19). Examples of grit (1355, 1323), conglomerate (1326) and shale (1322) will be found in the cases (y. p. 56). Great intrusive masses of plutonic rock, like the granitite of Newry, and that of Crossdoney, near Cavan, were intruded into these rocks in post-Lower- Silurian and possibly in some cases in post-Upper-Silurian (Devonian) times, and at a later date masses of not less importance like the granites of Mourne and Slieve Gullion, with their associated complex of other igneous rocks («. page 75, &c.). These intrusions have produced a very marked contact alteration in the sedimentary rocks which border the granites both in the Newry area and at Crossdoney {v. page 60). An isolated patch of Silurian strata at Desertcreat, near Pomeroy, is of great interest owing to the number of fossils from it described by Portlock. Whilst the lower beds contain an undoubted Lower Silurian fauna, the upper beds yield Graptolites Avhich have enabled Lapworth to correlate them with the Lland- 62 tTLSTEK. [case XIX overy or Tarannon rocks. Tliey are chiefly green, fossiliferous, slates occasionally passing into argillaceous limestone (801), inter- bedded , ■with flaggy sancfefone« axi^:' conglomerates. About Lisbel- law in Eermsinagh both Lower and Upper Silurian rooks have been mapped. The Lower are , hard splintery, ^^a and the marine clays of the Lias, are met with near Lough Foyle, to the north of Lame, and near Belfast. They are light green and grey, slightly calcareous, mm-ls, CASE XXI.] J artASSIG AND. CRETACEOUS ROCKS. 67 followed by dark-bluisli arenaceous shales (910), and limestones (809), containing the usual brackish-water fauna, including Avicula contorta, which sometimes makes up whole beds of lime- stone. The Series is never more than 100 feet, and seldom over 20 feet in thickness. Case XXI. — The Jurassic SysTEM, -._ The Lias (Sec. 2). — This Series consists of stiff blue fossiliferous clays (626, 810), bla,ck indurated shides (841), and blue' iharls interstratified with dark limestone (811, 832, 5, 1041). ATjout Lame the following zones in ascending order ai-e recognisable : — ' Ammonites planorhis,' A. ahgulattxs, A. BucMandi, and possibly A. margaritatus. The total thickness amounts to 35 feet. ' Near Portrush the clay is much baked by the intrusion of basalt {v. case XXVI.) Case XXI. — The Cretaceous System. The TTpper Greensand (Maji F ; Sec. 2 ; P. 69).— A great gap occurs at this point in the sequence, and the succeeding deposits are the lithological and homotaxial equivalents of the Upper Green- sand of eastern and southern England, although probably they are later in actual date. The basal bed is usually pebbly, and a conglomerate a foot in thickness is often met with. This passes into a compact sandstone speckled with dark green grains of glauconite (812), which, becoming oxidized, give the upper beds a reddish colour near Lame (836, 7). Only 10 to 12 feet thick here, aixd occasionally dwindling to a few inches in the north, it thickens out to 70 or 80 feet near Belfast, where there are green m,arls and sands (813, 872) surmounted by a conglomerate known as the " mulatto stone." Dr. Hume and M. Barrois conclude that the Hibernian Greensand was not deposited contemporaneously with the English rock of the same name, but was laid down in Lower and Middle Chalk time near the shore of the Chalk Sea. The Chalk (Map F ; Sec. 2 ; D. 24 ; P. 59, 64, 73).— This is great mass of hard white, compact limestone (632) occasionally marly and ironstained (633, 627), and with seams oi flint about four feet apart (814). The organic origin of the Chalk is clearly seen in microscopic sections which are full of foraminifera from -^-^ to -g^ of an inch in diameter, and similar tests have been found by Mr. Wright in the siliceous dust inside the hollow flints. The flints themselves (635, 8) are tabular or irregular bodies made of almost pure silica ; they have an a,brupt junction with the Chalk, and have almost certainly been deposited in it from solution of silica in water, as shown by the replacement in flint of organisms which while living undoubtedly possessed sbells made of carbonate of lime. Where the Upper Greensand is absent there is a pebble bed which forms a base to the Chalk (640, 1, 2, 3), clearly indicating that we are here near the margin of the Chalk Sea. Separating the Chalk from the E 2 68 tJLSTER. [cases XXI. & XXit overlying Basalt of the plateau there is generally a gravel made of flints (639) -which are often reddened and altered by the heat of the basalt when it flowed out on the surface (D. 13, 23). The fossils in the finer beds of this stratum are mainly rolled forms derived from the Chalk. The Antrim Chalk is about 150 feet thick ; it forms a base to the plateau, but occasionally it rises into important hills when protected by a capping of basalt. It appears to belong to the division of the Upper Chalk, and mainly to the highest zone characterized by Belemnitella mucronata. The hardened nodular bands indicate the presence of a shore line, while the transgressivc overlap to the south, as M. Barrois has pointed out, indicates that in all probability this shore line was situated in the direction of County Down. Case XXII. — The Tertiary Group. The Volcanic Eocks of Antrim (Map Fj Sec. 2). — After the denudation of the Chalk and previously formed strata the north- east of Ireland became the scene of wide spread volcanic activity. The earlier or lower sheets of Basalt amount to 450 feet in maxi- mum thickness and, resting on an eroded surface of Chalk, rise into tabular lulls 1,200 to 1,300 feet in height, while the valley sides are terraced by the outcrop of the great sheets of lava which have been carved away by streams since early Tertiary times (D. 34 ; P. 73, 74, 76). The lavas exhibit tabular, spheroidal (D. 18), and columnar jointing (D. 31 ; P. 52, 53, 56, 64, 67, 72) ; their general character will be described on page 78. Occasional beds of agglomerate and tuff occur, and the old vents of eruption, filled with masses of coarse agglomerate penetrated by basalt dykes, may occasionally be made out, as at Carrick-a-Raidhe and Tieveragh Hill (P. 71, 74). Masses of Bhyolite occur at Tardree and Templepatrick, Ballymena, and near Moira, and are intrusive into the Lower Basalts. They were probably exposed to denudation before the Upper Basalts were laid down, for beds of rhyolite gravel are found between the Upper and Lower Basalts. The Associated Sedimentary Deposits (Map F ; Sec. 2). — Between the layers of the Lower Basalt bands of clay and iron-ore are of frequent occurrence (D. 32), but they become of great importance between the Upper and Lower set of Sheets (D. 13, 23, 24, 27 ; P. 59, 68). They consist of basaltic ash beds (1042, 3) and trachyte gravel (980, 1 , 3) passing down to fine clay, often full of fossil plants (984, 5) and seams of lignite as at Ballypalidy, famous for its leaf-bed, and to bauxite (839, 988, 990), a clay rich, in hydrated oxide of aluminium with some iron, sometimes used in the preparation of the former metal. Mr. Kinahan names the slightly ferruginous clays Alumyte ; they contain 42-52 per cent, of alumina, 1-1-5 of iron oxide, 13-27 per cent, of sUica, and 18-27 per cent, of combined water; consequently, as he points out, they do not correspond with any of the principal types of CASE XXII.], TERTIARY ROCKS. 69 French bauxite, but resemble more the wocheinito of Carniola. At other times there are bands of clay (U. 29), and lithomarge (987), passing into ochre and then into a rich h-on-ore (D. 48). This is sometimes a clay saturated with hydrated iron oxide, but often the iron is gathered into pisolitic concretions of haematite in an ochreous paste (993, 5, 8, 9). The iron ores contain from 35 to 40 per cent, of metallic iron, and are worked still to some extent, while the ochre is extensively used. There is little doubt that this series of deposits represents the subaerial denudation of the older volcanic rocks ; it was deposited from streams, lakes, and the soil, and was afterwards covered up by the flows of Upper Basalt. The plants referred to above indicate that the volcanic activity probably dates to the late Eocene or Oligocene period, The Pipeclays of Lough Neagh which have been considered to be Pliocene in date are either the expansion of those just described or else earlier than the Basalts in date. Their relation to the Basalt is uncertain, but they probably underly a great deal of the area of Lough Neagh. They are white clays, sometimes useful as a pipe-clay, variegated by red and greenish mottling (2789), and containing fossil plants usually preserved in carbonaceous material, but occasionally partly converted into silica. Silicified wood is very common on the shore of Lough Neagh and has been widely dispersed by glaciation (v. case 50). This wood opal resembles that preserved in the basalt of the Giant's Causeway, from which it was once supposed to have been derived, but Mr. Swanston has now proved beyond doubt that the Lough Neagh clays have been its source. The clays containing Mytilus (once referred to Unio) have been shown by Mr. Clement Reid to contain scratched fragments of basalt and worn fragments of sUicified wood ; they underlie other boulder-bearing clays, and must be classed with the Pleisto- cene deposits. Case XXII. — The Pleistocene System. The Lower Boulder Clay. — The North of the Province of Ulster it is which gives the best evidence of two directions of main glaciation, the first from S. orS.E. to N. and N.W. outwards from the great .snow field which exteuded south-westward from Belfast and the second from N.E. to S.W. when the Scottish ice invaded the coast of Antrim and travelled across the country and out by the western coasts. The Lower Boulder Clay (D. 25 ; P. 73), the product of this glaciation (2790), extends in ridges and sheets to heights like 1,300 feet in the Spen-in Mountains and elsewhere. Shells are found in the clay at Mufi' and Bovevagh, and the clays are at times useful for brick -making. The Middle Sand and Gravel is cuirent-bedded and shell-bearing, and occurs in terraces up to 600 feet above the sea in Antrim. The Upper Boulder Clay, well developed in Tyrone, is sometimes 50 feet in thickness and extends to a height of 850 feet. The 70 ULSTEE. [CASE XXII,, gravels of Some eskers are apparently covered by Upper Boulder Clay and many have erratic blocks on them. Some of the erratics are very large, as for instance the " Butterlump " Rock on the east coast of Down which measures 20 feet by 15 by 15 j. a picture of this. by, Du Noyer will be found on the walls (D. 45), and also a photograph (P. 79). Another block has the same breadth and height but is- 30 feet long (see also P. 84). There are local moraines in many places, for instance in the Moume Mountains and on the granite range of Barnesmore, and some of these moraines dam up existing lakes or others which are now filled up with detritus and form alluvial flats. There are Eaised Beaches at heights of about 25, 50, and 75 feet above mean sea level with old raised cliffs and sea stacks (P. 57) above the highest tides of the present day. In connexion with some of' these beaches kitchen-middens, or old refuse heaps of shells, bones and charcoal, associated with flint implements and chips of undoubted human workmanship, have been obtained, and in some of the high level river gravels palaeolithic flint weapons have been discovered. Mr. Praeger considers that the Estuarine clays found beneath the sea level on many of the shores and in the Loughs of the North of Ireland were formed by the depression which gave rise to the highest of these beaches. Resting on the Boulder-clay comes, first of all, red sand which is considered to be equivalent to the eskers; then grey sand andpeat containingremains of Megaceros (the " Irish Elk ") and probably equivalent to the shell marls so frequent under peat bogs and marked by containing' Megaceros ; then follow the clays, the lower characterised by Scrobicwlaria piperata with a littoral shell-fauna, and hence not deposited in deep water, and the higher deposited ti'anquilly in deeper "vt-ater and yielding Thracio, convexa and other shells which indicate a depth of 50 to 80 feet. The fauna is of a slightly more southern type than that inhabiting the shores at the present day. The river alluvia yield brick-clays, and that of the River Bann contains numerous diatoms, and is so siliceous that it is mixed with clays for brick making. Blown sand, intakes, and travertine deposits also occur. The bogs are wide-spread, sometimes yield bog iron-ore, and occasionally conceal the relics of 'old lake-dwellings or crannoges in which stone and bronze implements, and some- times gold ornaments, have been found. 2.— THE IGNEOUS ROCKS OF ULSTER. The Northern Province is unrivalled in Ireland for the quantity and variety of igneous rocks which it contains, all types being represented,, from the most ancient and foliated types, to the most recent volcanic outpourings in the British Isles. Case T. is reserved for the known Tertiary lavas of the great Antrim plateau, ■ with a few older rocks from the same district, and the rest of the igneous rocks are placed in c;ise E. For this reason CASE E.] IGNEOUS ROCKS OF. THE NORTH WEST. 71 it will be necessary to depart somewhat from the usual order of description from North to South, in order to treat the great crystalline areas of the West first ; we shall then proceed towards the East and South, and conclude with a, description of the Tertiary and older rocks of Antrim and the neighbourhood. Such a description cannot however be strictly historical, for even in the areas of most ancient rooks, there are found others of much more recent date, including even Tertiary, or at any x-ate post -Carboniferous, dykes. The following areas will be dealt with : — (1) N. W,. Donegal, (2) Barnesmore and the Blue Stack Mountains, (3) the Saphoe region, (4) Crew and Park in Derry, (5) Slieve Gallion in Tyrone, (6) the rocks in thewestern and central tracts of Old Red Sandstone and Carboniferous rocks, as at Omagh, (7)' the Coast of Down, (8) the granite areas of Newry and Slieve Gtdlion, (9) the area of Crossdoney and Cavan, (10) the Mourne Mountains and Coasi, (11) The older igneous rocks of Antrim, (12) the Antrim plateau. Case E. — The North-west Granite Area (Gweebara). (Map E ; Sec. 26). A broad band of Granite stretches from Malin Head in a south-westerly direction to Gweebara, and comes again to the surface at Glenties. This mass has been the subject of elaborate investigation by Scott and Haughton, who determined that it had the composition of a hornblendic granitite with two felspars (2796), miorocline and oligoclase (2339), quartz, black and occasionally white mica, hornblende^ sphene (2340) and often garnet. The felspars are white and pink (2294), the latter often being large and porphyritic (2806). The authors mentioned above showed that the silica percentage of the rook varies from 72 at Doochary Bridge to 55 at Ardara, on the edge of the mass. It is frequently penetrated by veins of pegmatite (2297, 2308) ; along certain bands, as at Barnesbeg, it is richly gametiferous (2302). These Dands are on the strike of limestone bands caught up in the granite and highly metamorphosed by it, crystalline calcite, garnets, and other minerals being developed (•u. page 57). This gave rise to the idea that the granite had absorbed the material of the limestone and acquired a different composition in consequence. Portions of the granite are beautifully foliated, near Glen (2296, 2299), and else- where (2291), where the rock is a biotite gneiss, often containing rounded crystals of felspar (2299), or else has a granulitic aspect. It has been thought t}iat there was a perfect transition from the surrounding schists through the gneiss into massive granite, a passage which was supposed to indicate that the granite represented the last and highest stage in the metamorphism of the sediments. The reverse is probably the truth, the granite where acted on by great earth-movements, either during or after consolidation, has itself become foliated. Many beautiful varie- ties of this rock and of the granitite of Barnesmore have been quar- ried for polishing. Felsites (2311), coarse diorites (2312, 3), 72 ULSTEB. [case E, lamprophyres (2805), massive amphibolites (2315), and epidiorites (2318) are common intrusive types in the granite and the border- ing schists, and augite-syenite containing biotite, from Three Tops Mountain, has been described by Dr. Hyland. Porphyritic olivine-lasalts with quite fresh minerals and possibly of Tertiary age also freely occur (1762). A remarkable spheroidal granite occurs at Mullaghderg near Dungloe. The main granite is of the normal type, but it is full of flattened spheroids from 1 to 4 inches in diameter which possess both radial and concentric structures. The nucleus of these bodies consists of a gi-anular aggregate of striated felspar (oligoclase), with unstriated orthoclase and some quartz ; outside this comes a zone of oligoclase with radially grouped crystals, free from quartz and with occasional flakes of biotite, and over 12 per cent, of iron-ore. This spheroid-bearing rock has been d(!Scribed at length by Dr. Hatch. Polished and unpolished specimens will be found in case XXXIII. Mr. R. H. Scott gives a long list of minerals which have been obtained from the granite and rocks in its neighbourhood, and amongst them schorl (indicolite), beryl (2307), molybdenite and apatite are noteworthy. Case E. — The Barnesmore Granite Area. The Barnesmore or Blue Stack area consists of a true graniiiie with black mica only. The felspars are microcline and plagioclase which embed well-formed, small, crystals of orthoclase. The rock is pink in colour, and contains much quartz (1470) ; it may conceivably be of Tertiary age. It is penetrated by very fresh and'probably recent dykes of /)ifcAsto?ie, andesite,a.nA dolerite, which have been described by Professor Sollas. The pitchstone (1468, 2335) is black and resinous, sometimes vesicular, and porphyi'itic ; the brownish glassy base contains, according to Professor Sollas, slender needles of pyroxene, minute stellate crystals, and magnetite dust, and in it are embedded porphyritic'crystals of sanidine, quartz, and plagioclase. The augite-andesite is made up of plagioclase felspar, pale green pyroxene, and magnetite embedded in a glassy vesicular matrix. The doleritcs are fresh and ophitic with plagioclase felspars set in purplish-brown augite and con- taining much olivine which in most cases is not in the least decomposed (1464, 1478). Most of these rocks contain porphyritic felspar and they penetrate the granite, schLsts, and even the Carboniferous rocks of the locality. The great dolerite mass near Donegal (1481), pierces the lower Carboniferous Sandstone. It is a very coarse ophitic olivine-dolerite with lai-ge masses of augite which enclose felspars and olivines ; all the minerals are j)erfectly fresh. The schists are traversed by dykes of micaceous felsite (1474), probably off-shoots from the granite, and epidioAtes, containing much hornblende (1457), and often converted into micaceous hornblende-schists bearing secondar'y quartz and albite, (1458). case e.j igneous rocks. 73. Case E. — Kaphoe Area. (Map E.) The schists of Raphoe are pierced by numerous homblendic microgranites (1900) frequently showing porphyritia crystals of orthoclase in a microorystalline matrix (2817). At Clondermot (2815) there is a dyke of vogesite or syenitic lamprophyre, a pink rock with acicular hornblende, showing microscopically well formed crystals of hornblende and orthoclase with a small quantity of interstitial quartz crystallized between them. ^Numerous epidiorites ai-e to be found at St. Johnstown (2321), Convoy (2323), and near Raphoe (2325) ; they are grey in colour and certainly are highly felspathic and calcareous. Case E. — Crew and Park. There are intrusive felsites (1573) about Crew in Tyrone, and felsite breccias (1576) which seem to indicate contemporaneous volcanic activity ; similar felsites are found at Park in Derry. The chief igneous rocks however amongst the schists of Derry are cpidim-ites, often very coarsely crystalline (1484), and still retain- ing their ophitic structure, although the minerals have been changed. In some the original pyroxene appears to have been diallage, but it and other pyroxenes are now generally converted into actinolite or fibrous amphibole in aggregates. Case XXXII. — Slieve Gallion. A plutonic complex containing several interesting rock types occurs in Tyrone, about Slieve Gallion and Kildress. The pro- minent types are coarse granites more or less foliated, and passing into quartz-diorites. Both types of rocks frequently contain blue quartz (2820, 2337) together with abundant hornblende, and some mica, chiefly biotite (2337) ; as usual there are also intrusive dykes of epidioriie passing into Iwrnblende-schist. At Athenree, and Termonmaquirk near it, there is a very beautiful gabbro (1763) exhibiting many of the variations shown in such areas as the Lizard and the Ayrshire Coast where gabbros abound. The pyroxene is present as large, flat crystals of diallage with small metallic-looking plates deposited along its cleavage planes so that it has a glittering bronzy lustre in hand sjiecimens. This mineral varies much in size, some crystals being ^^-inch long (3481), while those in other specimens may be 1 or 2 inches. When this great size is attained the diallage makes up the bulk of the rock (3480, 736), as it does in the diallage rock from Lendalfoot in Ayrshy.'e. A plagioclase felspar is usually present, sometimes set ophitically in the diallage, and the last mineral is frequently altered into a mass of fibrous actinolite. A fresh ophitic olivine-dohrite is to be found at Gortacloghan (1764). 74 ulster. [case e. Case E. — Omagh, etc. A miscellaneous group is next placed together, because the rocks, for the most part, are interberlded with, or intrusive into, the Old Red Sandstone and Carboniferous rocks of central Ulster. First come the melaphyres or altered olivine-hasalts about Omagh and Recarson — intrusive into the Old Red Sandstone and older rocks. These are purple rocks with no visible porphy- ritic ingredients except shining opaque crystals, with a bronzy lustre and colour, looking at first like specular iron but in reality referable to a mineral recently described in America as iddingsite. These are clearly pseudomorphs after olivine, a mineral in which the rock must have been rich. As they are set in a ground of plagioclase laths -with augite, and possibly some olivine, the rocks may be classed as olivine-hasalts (234:4). About Cappagh, south of Pomeroy, there is found a group of altered hypersthene-andesites or porphyrites, red or purple rocks (2345), with a very marked ilow- sti-ucture (2346), almost certainly lavas interbedded with the Old Red Sandstone of that district. Scattered over the Province are many dykes of perfectly fresh basalt and dolerite, like many already described as certainly post-Carboniferous and probably Tertiary in age. They are mostly ophitic, with plagioclase felspar laths embedded in augite, and with porphyritic crystals of olivine, often quite fresh and unaltered. A zeolite, possibly analcime (1347 from Armagh) occurs as the ultimate product of consolidation or else as a secondary product deposited in place of or between the felspars. The dolerite at Lisnaskea contains very beautiful augites coloiirless internally but deepening to an intense purple brown or even black tint at their planes of contact with the felspars (1419). The great sill (the " Whin Sill " of Ireland) intrusive into the Yoredale rocks of Fermanagh, north of Lough Melvin, is a porphyritic dolerite, rich in olivine, but it appears to have been folded, subsequently to its injection, together with the Carboniferous rocks which contain it (1505). If so it can hardly be of Tertiary age ; but any more certain evidence than this is wanting. Case E. — Coast of Down. The contorted Lower Silurian rocks of County Down contain a number of igneous rocks which, like the sediments, connect this area with the Southern Uplands of Scotland. The chief of these are Iwmprophyres or Tnica-traps belonging to the group of minettes and kersantites. The usual mica is brown, probably biotite, but it is often bleached and zoned, the interior being lighter in colour than the exterior ; occasionally the interior is darker than the exterior, and where that is the case there is generally a black margin to the crystal (2354). The hornblende, which is generally present, is also usually zoned. The matrix of the rocks consists of an aggregate of small, stumpy, usually well formed, crystals of CASE E.] IGNEOUS BOCKS OF DOWN. 75' felspar, but they are often so much decomposed that it is impossible to say whether orthoolase or plagiocl^se predominates, while at times the two constituents are present in equal quantities. The rocks are in thin dykes, often muchi twisted and altered, and are, usually to be seen on the sea coast ; a few, however, have . been traced inland. A rock, occurring some miles N.W. of Dqwui. patrick (2356), may be called hornblendic miaette,' those three- miles N.W. of the same place (1906) and on theshore at Bally- waiter (1903) are hersantites, at times augitic, while that from Dillon, S.E. of Downpatrick (2849), is a camptonite, and that from four miles W. of Killyleagh (Orossgar 1 2354) can only be. spoken of as a mica-trap. Case E. — The Newry Granite. The great mass of granite, extending from Slieve Croob to Newry and on to Slieve GuUion and Forkill, next claims a,tten- tion. It is a grey granitite without muscovite but with quartz, two felspars, black mica, and greenish hornblende (2357, 8). Much plagioclase felspar, probably oligoclase, is present, and this some- times increases in quantity so much that, though normally a potash-granite, the mass locally becomes a soda-granite. Sphene and apatite are abundant, and the mica is so much altered to chlorite as to look green in a hand specimen. The rock is quarried for building ajid ornamental purposes at Goraghwood and Bessbrook (v. case XXXIII.) This great granite mass is intrusive into Lower Silurian rocks which are much metamorphosed along the junction plane. Remarkable rocks, which are said to gradviate into the granite, have been collected from Slieve Garran (2363, 4); they are not improbably enclosures, either of the nature of segregations or else brought up from below by the molten granite. They are dense black rocks showing, when fresh, biotite, diallage and apatite in great quantity, augite, and both green and brown compact hornblende, often inter-grown together (2364). The diallage, however, gradually passes at its edges into actinolite, and one specimen (2363) retains hardly any diallage at all, it" having been replaced by fibrous actinolite. Parallel with the granite boundary or radiating out from it into the surrounding rocks, or even at times penetrating the granite itself, are dykes which have been mapped as elvanite, and which, judging from Professor Hull's description, vary from microgranites to qua/ftz-porphyries. Their matrix is microcrystalline or cryptocrystalline, and they contain crystals of orthoclase, oligoclase, mica, quartz, amphibole, and apatite. Close-grained basalt dykes penetrate the granite (2362), and one, of the glassy variety called tachylite, is found at Tullynasoo Movin.. tain in Slieve-na-largy, near Castlewellan (2853). It was desci-ibed by Mr Rutley as a glass, coloured brown by the minute dust which it contained, embedding crystals of magnetite, clouded dark bodies possibly made of magnetite dust, and spherical bodies which 76 ULSTER. [cases II. & E. have some of the characters of magnetite. Tlie specimen in the Survey Collection shows, in addition, skeleton-octahedra of magnetite, like those seen in slags, with tiny plagioclase crystals, often mere skeletons made of microlites, and radiating tufts of similar microlites. The analysis of the rock by Professor Haughton gave 55 per cent, of silica and the usual composition of a basaltic glass. A pUchstone, with a remarkable platy structure, occurs in the town of Newry (3330). It is a glass, coloured brown by tiny star-like groups of microlites and containing porphyritic crystals of quartz and orthoclase. The chief rock in Slieve Gullion is a \oTYih\eD.Aic microgranite (1904). Case II. — Crossdoney and Cavan. The granite mass of Crossdoney, near Cavan, corresponds with that of Newry in geological position and in many of its characters (1557). It is a granitite, sometimes augitic, passing towards the quartz-diorites, white or grey in colour, non-porphyritic, and contains about equal qviantities of orthoclase and plagioclase felspar. Under the microscope the felspars, mica, hornblende, and augite, when present, are all found to be idiomorphic and embedded in interstitial quartz in the coarse varieties(1568), in a microcrystaDine matrix in the compacter varieties (1555). Sphene and apatite are usually present. The augite is light green and edged with secondary hornblende, while in compact varieties the small micas aggregate round the augite crystals (1556). The mica is biotite of a deep brown colour, and it is frequently intergrown with the hornblende (1563). The rock is devoid of foliation, passes at its edges into fine-grained microgranite (1561) rich in biotite, and even into felsite, and while itself pierced by microgranite veins at its edges, it includes patches of altered sediments which it has caiight up and converted into hornblendic and micaceous hcrrnfels. It has exerted great influence on the sediments through which it has been intruded, and its contact phenomena have been dealt with on page 60. Case E.— The Mourne Mountains. (Sec. 1.) The granite of the Mourne Mountains is certainly much more recent than the two last described. It is a granitite with quartz often smoky in tint (2366), two felspars, orthoclase and albite, and green mica. The order of consolidation of these minerals is not that usual for granites, for, instead of crystallizing last and enclosing the other constituents, the quartz has crystallized first, taken its own crystalline form, and become embedded in the other minerals (2367). This is especially the case on the margin of the mass. This rock is famous for its geodes, which are hollow cavities or cracks lined and filled with the essential and adven- titious minerals of the granite ; thus quartz, albite, and orthoclase occur in some specimens (1905), beautiful crystals of beryl and CASES E & F.] IGNEOUS ROCKS OP DOWN AND ANTRIM. It topaz in others, and crystals of chrysoberyl, fluor, peridot, and gadolinite have been found. It is not usually porphyritic, but this aspect is sometimes seen (2371), when the rock would be a beautiful ornamental stone. The very characteristic scenery of the granite area is illustrated by Mr. Welch's beautiful photo- raphs (P. 93, 94, 95). The age of the granite is certainly later than the Carboniferous Period and it may possibly be Tertiary. It presents char'acters which link it with the Arran granites, and it is known to truncate certain basaltic dykes which are of Tertiary type, and probably belong to the lower set of lava sheets, although it is itself pierced by others of a simUar type, probably belonging to the upper set ; this would suggest that its ago is the same as that of the rhyolites to be shortly described. The coast-line to the east of the Mourne Mountains shows a great variety of igneous rocks. Micaceous quartz-porphyries (2855, 6), felsites (2859) which are hardly to be distinguished from the rhyolites to be presently described as occurring further north, andesites, basalts (2857, 2375, 6), and dolerites. Many dykes are composite, being tilled in with two or more types of rocks, such as rhyolite and andesite, or felsite and basalt (2857). Professor Cole has described an instance where the inti'usion of an acid rock (eurite) has caused the melting and absorption of some of the con- stituents of a previously intruded intermediate rock (andesite). Amongst the basic dykes, Patrickson and Portlock discovered examples with variolitic structure near Annalong, and these have been re-discovered and described by Professor Cole (1750). This type of rock is generally green, with purple, spherical bodies, or varioles consisting of radiating crystals, scattered through it. This structure appears to be visible only at the edges and probably at the top of the dykes ; such dykes are likely to be of very recent date. A great dyke at Rostrevor is much worked for paving-setts ; it is an uralitic diabase or epidiorite containing plagioclase, augite, uralite, viridite, and magnetite (1765). Pro- fessor von Lasaulx termed the rock eucrite. Case F. — The Older Igneous Rocks of Antrim. (Map F; Sec. 2.) — A beautiful diorite of the type called camp- tonite by Rosenbusch occurs at Rue Bane Point, in Antrim, amongst the gneisses and schists. It contains crystalline hornblende and biotite in a decomposed felspathic base, which now includes much calcite and minute needles of hornblende (1896, 2825). Epidiorites also occur here (2347). A mass of quartz-Jelsite or quartz- porphyry (2836, 2351, 2) occurs to the west of Cushendall, and has provided by denudation a large proportion of the pebbles of the conglomerates at the base of the Old Red Sandstone of that locality (2834). It is a porphyritic rock, red, white, or black in colour, with abundant crystals of porphyritic orthoclase and some plagioclase, brown mica and quartz, in a close-grained ground- 78, ULSTEE. [case F; mass, -whicli is a folt of minute felspar needles. In a boss N.W. of Ciishendun, and in dykes on the shore, there occurs a bright red porphyritic, microgranite (2827, 2830). The phenocrysts consist of orthoclase, oligoolase, and quartz, set in a miccocrystal- line matrix. The porphyritic orthoclase crystals are beautifully zoned and often very large ; they contain, ophitically, numerous small, well-terminated crystals of oligoclase, which are usually arranged parallel to the outlines of the containing crystal. Biotite, more or less altered to chlorite, is a tolerably abundant constituent in some typesj, and it is sometimes present inside the large orthoclase phenocrysts. Case F. — The Volcanic Plateau of Antrim. • (Map F; Sec. 12.)— In this area the first rocks to claim attention are the necks, bosses, and dykes, the feeders from which vast floods of basaltic lava proceeded. Amongst the necks may be mentioned Slemish (2402), Tieveragh Hill (2396; P. 74), Scawt Hill (2403, 4, 5), and Carnmoney Hill (2418, 9, 2420; P. 71). The dykes penetrate all the older rocks of the district, Old Red Sandstone (2396), Lower Carboniferous rocks (the Great Gaw dyke, 2386), New Red Sandstone (2425, the Carrickfergus dyke), (P. 58, 60, 78, 89, 90), (Sec. 1 and 2), the Lias (2860) at Portrush, which is baked to a porcellanite without, however, destroying the fossils which it contains {v. page 60), the Chalk (2396, 2401), (D 28, 44 ; P. 59), and the Sheets of Basalt themselves (2388), (P. 77). Most of these dykes are the ordinary type of ophitic olivine-dolerite. The olivine has consolidated first in irregular grains, sometimes presenting a rude approximation to the crystalline form; then the iron ores, followed by the plagio- clase felspars ; lastly, the augite, in great ophitic plates, enclosing the previously formed constituents, especially the felspars. This order is not, however, always maintained, and is sometimes subject to the most remarkable variations. Thus the augite and felspar, and in one case even the olivine and felspar are inter- grown together like the felspar and quartz in micropegmatite ; while in two cases I have detected the olivine ophitically enclosing felspar crystals, proving that the felspar must have crystallized before the olivine in these instances. A very coarse-grained •dolerite (or gabbro) occurs at Portrush, the augite being in crj'stals an inch long. The felspar is, however, mostly replaced by a zeolitfe (2860, 1). In some dolerites from here the outer portions of the olivine crystals are deep brown in colour (2441). At Fair Head, too, there are coarse dolerites, with beautiful augite crystals, occurring in dykes, laccolites (P. 59), or sUls, intrusive amongst the basalt lavas or the Carboniferous rocks below (2389, &c.) In this rock Prof. Judd has described a peculiar feature which he calls glomero-porphyritic structure ; the porphyritic minerals a,re aggregates of anorthite and olivine, set in an ophitic matrix. CASE F.] THE TERTIAKY BASALTS. 79 A beautiful porpliyritic basalt, with bright glassy plagioclase crystals and small olivines, forms a dyke in the rhyolite of Carnearney Hill (2410). The basaltic lava flows are divided into two main sets, an upper and a lower one, with beds of ash, lithomarge, ochre, &c., between them, and indications, by denudation and deposition, of the lapse of veiy considerable time between them; There is no lithological distinction between the two groups except that on the whole the Upper are slightly finer in grain and more amygdaloidal than the LoWei;'. The rocks are mostly true basalts, soinetimps with porphyritic felspar crystals, but more usually quite compact. They are crystalline in microscopic sections showing a felt of long plagioclase crystals set amongst grains of augito which are usually colourless, but sometimes become brown at the edges, especially where bordered by iron ores. The only porphyritic constituent in the compact rocks is olivine (2868) ; occasionally there is a second generation of smaller olivines in the matrix (2441). Instead of being granular the base is sometimes ophitic on a small scale (2435) and at times the ophitic structure is so large that it is difficult to believe the rock is not an intrusive sheet (2429). Owing to the difficulty of separating intrusive sills from true lava flows where the two have a similar composition and appearance it is quite possible they may have occasionally been confused in the mapping. In the field these i-ocks are frequently columnar (3475) and columns will be found on the floor of the Survey room and also in a group in the adjoiiiing room (E 4), (D 31, 52, 55, 56 ; P. 43, 44, 64, 67, 72). Spheroidal structure is also very common (3472, 4), (D 18). The rook is frequently amygdaloidal (2436, 2442, 4, 5) the vesicles being filled with many minerals such as calcite, chalcedony, mesotype, scolecite, natrolite, galactite, stilbite, brewsterite, and a curious substance called hullite. Interbedded with the basalts and especially between the upper and lower groups are numerous ash. beds (2450, 2870), which j)ass laterally ipto iron-ores, ochres, boles, gravels, and bauxites (v. page 68). Considerable masses of agglomerate occur locally and are supposed to indicate vents of eruption, as at Carrick-a-raidhe (2447, 9). At Templepatrick quarry there is a sectioji which appears to prove that the rhyoHte of that locality is intrusive into the lower group of basalts. Now as it is certain that there are fragments of rhyolite in a gravel which occurs between the lower and upper basalt groups, the age o^ the rhyolite in this locaility seems to be definitely ascertained j it is later than the older liasalts into which it is intrusive, aiid earlier than the upper tasalts wljich rest upon fragments denuded from it. Thus the rhyolite indicates that a considerable lapse of time may have occurred betweeti the deposition of the Lower and Upper Basalts, to allow of denudation penetrating through the cover of basalt into which the rhyolite was intruded before actually reaching that rock itself. This '80 ULSTER. [case F, rhyolite is found at many localities but chiefly at Ballymeiia (2873), Tardree (2455) and Sandy Braes (2458), at Templepatrick (2463), and near Moira (386) in Down. It is possible that, although intrusive at Templepatrick, it may have flowed out at the surface as lava at some of the other localities. This supposition is suggested by the flow and perlitic structures, the glassy aspect, and other characters presented by the rhyo- lite at Sandy Braes and other localities. These characteristics can all be matched in the recent rhyolites of Hungary. The rock is acid in composition and contains 76 per cent, of silica. This shows itself in porphyritic crystals of quartz and sanidine which occur side by side with those of plagioolase felspar, almost certainly, al bite there being very little lime on the rock. Ferromag- nesian constituents ai-e rare, but biotite and hornblende have been noticed, together with magnetite, epidote, apatite, zircon, and sphene. Von Lasaulx detected tridymite in plenty as minute scaly aggregates. These minerals are embedded sometimes in a pure brown glass when the rock is a porphyritic obsidian or pitch- stone, but more usually the glass is crowded with minuts curved trichites or crystallites. The rocks are brown or greenish in colour and show their porphyritic quartz and felspar crystals clearly to the unaided eye (2874, 7). At Sandy Braes, where the characters just mentioned are best seen, the rock is often beautifully perlitic, a structure due to the shrinkage of the rock as it cooled, and which has afiected not only the glassy base of the rock but the enclosed quartz crystals. The grey " trachytic " varieties more common at Tardree and Templepatrick (2464) are quite similar in their porphyritic constituents, but these are embedded ina matrixnotnow if ever glassy, butmadeofafeltoforthoclasemicrolithsassociated with quartz and probably tridymite (2882). Sometimes the matrix is cryptocrystalline and the actual character of its components cannot be ascertained (2881). Occasionalh' the cores of the porphyritic crystals are striated felspar completed by the addition of zones of orthoclase (2463). When the rock has undergone a great deal of decomposition it becomes warm brown or red in tint (2459, 2460), and opal is not infrequently present in these decomposed varieties (2875). The flow structures are often very beautiful (2880) and are due to bands of different colour, hardness, or resisting power, to streaks of microlites in the glass, to the alternation of glassy and stony bands, or to bands with microlites alternating with those possessed of cryptocrystalline structure. Of the upper lava-sheets but little remains to be said ; they are mostly basalts, compact, and with a minute crystalline structure (3473, 2466). Some, however, are coarser and show ophitic relations in their principal minerals ("2467, 9). These rocks rest on ashes and in hollows denuded in the older set of lavas. CASE XxVlI.] SiLUIliAN ROdKS Of' MITNSTER. 81 4.— ntUNSTER. 1. GENERAL ACCOUNT OF THE HOCKS. The rocks of this Province are traversed by a series of folds ■which trend from a point a little north of east to one a little south of west. These folds bring Silurian rocks to the surface at the north-east, south-east, and west of the Province, but over the rest of the area only Devonian (or Old Red Sandstone) and Carbon- iferous Rocks are displayed in alternating ridges and troughs, crossed and truncated by a second set of slighter folds trending north and south. The mountain tracts usually occur on the anticlinal lines, where the Devonian and Silurian rocks make their appearance, and particularly where — as about Killarney — these are associated with igneous rocks. The Coal Measures are to be found in Limerick and Tipperary, Lower Carboniferous rocks only being left undenuded on the southern synclines, amongst which, and the associated Devonian rocks, some mineral veins occur. The succession of rocks in Munster may be thus stated, in descending order ; — Systems. Igneous Rocks. 5. Pleistooena, , f i. Carbonileroas, 3. Old Bed Sandstoit^/ 2. Upper Silai'iait, . 1. Lower Siloriad, . Bpa Clays, &c. 'Coal Meafjures, > • Millstone 6rit, { Yoredale Series, Carboniferous LimSstotie, .Carboniferous Slate, iSiC, (■Upper Old Bed Sandstone, . ) Lower Old Bed Sandstone and i (. Dingle Beds. ^ Intrusive and Intef- bedded Bockd, Intrusire and Intdf- bedded Bocks. Intrusive and Inter-- bedded Books. Intrusive and Inters bedded Books. Case XXVII The Siluktan System. The rocks of this System occur inside a series of inliers sur- rounded by Old Red Sandstone^ dotted about in the wide area of Carboniferous strata of the Nortb-eastem and. Central parts of the Province, in the area of ClogJier on the west, and of Waterford to the east. The following areto der/oand deiicription :— (1) Lough F 82 . MUXSTER. [case XXVII. Graney ; (2) Slime Bernagh, the Silver-mine Mountains, Slieve- Felim, and the Devil's Bit ; (3) Slieve Galty ; (4) Slievenaman ; (5) The Gomeragh Mountains ; (6) Clogher Head and Dingle. Every wliei-e the rocTjs' are greenf gi&j', 'or blue grits, slates, and flags, with beds of sandstone, rare limestones, and black slates. The slates are especially quarried and 'jitilized in Clarfe, Cork, Kerry, and Tipperary. At Lough Graney the beds answer this description (1746, 7) ; they are imperfectly cleaVed, and, about Scalpnagown, contain beds of volcanic ash and breccia, and'mabses of felsite, andesite, Etnd amygdaloidal diabase, some of which'' are intrusive, btit others are undoubtedly la'vas of fconteinpcJrfeirieOus date {v. page 90)."' N6 fossils have hitherto b'efen foulid in these rocks, and their exact age is unkiiown. Ini the Slieve ^efnagh r^nge dcetlr ' conipact green ^ri<« (1676), purple' (1682)' tod gre^H slates (1666, 16T9),' quartzo-felspathie sandstonesiX'^^O), with olive arid red clay rocks ; fossils are fairly abufidSa^J Workable slates are quarried at Killaloe and elsewhere' in Slieve Bernagh. From Sixmilebridge, Ccenog'j'ap^its send Dicellograptus have been obtained in beds which must be of Llandeilo age, while the presence of Llandovery, and' pethaps higher, rocks ' in the neighbourhood, is indicated by the presence of Cyrtograptus, Monograptus priodon, Petraia, Cardiola interrupta, Euomphalus funatws, Atrypa marginalis, and other forms at many localities in the Silvennine and Slieve Felim Mountains. Copper mines have been worked in these beds at Laokamore, and graphitic anthracite occurs in the Silurian beds of Upperchurch. The exact order O'f succession being imknown, it is impossible to give even an approximate estimate of the thickness of rock. Slieve Galty is made up of hard green or grey quartzose grit (1699) and dark olive and black, sandy, shales (1701, 1702), from which no fossils are recorded. Jukes suggested that the western group of dull green and purple rocks in Slievenaman might possibly be Cambrian, while the blue and grey slates and grits, with dykes of diabase and felsite and beds of volcanic ash, to the east, were probably Lower Silurian ; but the fossils since collected from the western group prove that it also is Lower Silurian. In Waterford (Sec. 50) pale grey or purplish shales with thin grits (916), narrow bands of limes- tone, and thin beds of black s/j«?e (848, 849), in which numerous graptolites are found, occur atTramore and at Gibbet Hill. These include Leptograptus flaccidus,? Dicellograptus sextans, Dipln- graptus ^.mucroiiatus, Glimacograptus ijncprnis ?), Mid Dicrano- graptUiS ramosus, which indicate the Llandeilo age of the rocks. These beds compare with, those of Sixmilebridge on the one hand, and of Ballymoney, near Gorey , on the other. Judging by the lists of fossils given by Mr. Baily,' it would appear that a &e- stone, approximately equivalent to that of Llandeilo, is present in the series, and that the liver-coloured conglotnerates And shales interstratified with volcanic rocks (v. p. 112), and associated with pale grey calcareous grits and flaggy impure limestone, con- CASES XXVit &L SXVIII.] S1I.URTAN ftOCKS. 83 taining' Trilobites, are of Bala age ; there would appear, however, to be no, Upper Silurian rocks in the area. This district contains an enormous amount of intrusive rock, which will'be refei'red to on page 89, and associated with the igneous rocks are the veins of copper ore worked at the Knockmahon mines. The remarkable group of Silurian rocks in the Dingle promon- tory has been broken up by Jukes and Du ISToyer into the follow- ing divisions, given in descending order :— 3, The Croaghmarhin Beds = Ludlow Series. 2, The Ferriter's Cove Beds =: Wenlock Series. 1. The Anascaiil Beds == Llandovery? 1. The Anascaul Slates are black and glossy (746), occasionally red or green, vniih flags. (1276) and a few beds of limestone (743, 744). It has been ; suggested, that, the latter may be of Bala age, butthebvillsLof . the fossils are such as are obtained from Llandovery, rocks. Their relationships with the rooks of the west of the promontory, are obscured by old Red Sandstone, but it is not , unlikely that the barren sandstones and _/?apBto«es with br^hti.red «AaZes, dipping under the Series next to be described,- and ■ called. the Smerwick beds, may be their equivalent in point oftage. They appear to be 2,000 feet thick. 2'. The FerritersCove Beds begin with conglomerates, followed by greepjsandy shales, interstratified with beds of fel spathic ash and agglomerate, and several lavas consisting chiefly of nodular feliite {v. p. 91), succeeded by red somdstone and slate. . They are full of typical Wenlock fossils («. page 112), including BrachiopodS' aoid, Trilobites, and are 2,500 feet thick. ,, , d.The^Groaghmarhin Beds are^as^s (79?) and grriis, occasionally with,tr£M3ks of moljuscs pr annelides (1275); tliey.are 1,000 feet thick, and contaii;i fossil^ of Ludlow and Aymestiy affi,nitie.5. Thepe rocks are much folded, and even in places inverted. Cases XJNII and XXVIII.— The Old Red Sakdstone; This is the most important rock System in Munster, and it has beeil inapjtfed under the head of three principal divisiOns^^D ingle Beds, Lower Old Red Sandstone, and Tipper Old Red Sandstone. FoT' purposes of description here it will be best to use only t^b' divisions; a Lowei-, including the Dingle Beds; for those rocks which are conformable to the Ujaper Silurian Avhen- it is present, but' generally unconformable to the Lower Siluriari; and an Upper (the Yellow Sandstone Series) which passes up conformably into the Carboniferous rooks, but usually rests on the Lower 01t( Red Sandstone, Dingle Beds, or anything older, with extreme unconformity. ; •■ ' The areas into which the description cart cofaveniently be divided, are the following : — (1) LOugh Graney ; (2) Slieve Bernagh : (i) Slieve Felim and the Devil's Bit; (4) Knochfeerirm ; (5) Slieve' f2 84 MONSTER, [cases xtvit. k :^jcVnfi Oalty ; (6) Knoch'niidldown Mountains ; (7) Dingle ; (8) Iveragh and Killa/rney ; (9) Glenga/rriff ; (10) South and West Cork ;■ (11) East Cork and Waterford. The same broad characters are recognisable throughout the whole range of these rocks. Deep red, liver-coloured, and chocolate, sandstones, conglomerates chiefly made of quartz pebbles, green and grey greywackegrits (Dmgle type), green, grey, and blue slates, and occasional seams of very impure sandy limestone, called corn- stones, which ai'e sometimes conglomeratic. Organic remains are rare, a few Fish and Plants being all hitherto discovered. The rocks have almost certainly been formed in great inland lakes. The upper division is made up of yeUow and reddish, rusty, sandstones, with plant remains and occasional freshwater shells. About L. Graney 800-1,100 feet of Upper Old Red Sandstone unconformable to the Silurian, and containing fossil Plants, occur. There is a soft red sandstone or breccia, often a eornstone, at the base, filling up the denuded hollows in the Silnrianrocks, and on this come red and yellow sandstones (1660, 3), shales, flags, cornstones^ and conglomerates of increasing importance towards the North (1662,5,1749). On Slieve Bemagh there are yellow and red: quartzose grits (1668) and sandstone (1685), with sliales andflcys 1,300 feet thick, but thinning to 450 feet in the South-west. At Slieve Felim the rocks are unusually calcareous, and consist of cornstones with yellow (1017), purple (1016), and white (1014), sandstones; the Series thickens from 800 feet in the North to 1,500 feet in the South. The Upper division alone is present in these areas and at Knockfeerina (map G), where it is pierced by "necks" of volcanic rock and associated with ash beds («. page 95). At Slieve Galty the Lower division begins to come in and is from 3,000 to 4,000 feet thick, made up of thick beds of red conglomerate, covered by red and liver-coloured sandstone, the unconformability of which to the Silurian rocks is shown by their containing pebbles derived from them. The Upper division contains plant remains, is 800-1,000 feet thick, and consists of yellow (1705, 1035) and brown-banded sa»ic?- stones (1707). The Lower division in the Knockmealdown Mountains has much tha same character, but is less conglomeratic, aud 4,000 to 5,000 feet of rock are seen without the base being reached ; where the base is seen to the east the division seems to be thinner ; the top 1,000 feet, containing yellow or white sand- stones and conglomerates (759, 1036), are mapped as the Upper Old Bed Sandstone. In the Dingle Promontory the lower beds of the Old Red Sand- stone (Dingle beds) rest with apparent conformity on the Croagh- marhin (Ludlow) rocks, although there are some facts difiicnjt to account for on this theory; they attain a thickness of at least 10,000 feet. Amongst the green and purple grits (662, 5) with slates audi cornstones (756), all unfossiliferous,' occurs a conglome" rate, that of Park more, containing pebbles of grit, horns tone, slate, ash, and limestone, some of the fragments bearing Llandovery CASES THE OLD RED SANDSTONE. S5 XXVII. & XXVIII.] fossils, which have apparently been derived from the denudation of Silurian rocks. The Upper Old Red Rocks rest with marked unconformity upon everything below them, and in the Oaherconree Mountains an old cliff of Silurian rock, 500 feet high, is apparently buried up by the accumulation of the Upper Old Red Sandstone. The rocks are of the usual character, but they contain a great band of conglomerate called the " Inch conglomerate " (748, 9, 750, 1 ; 661, 883, 1277), made up of fragments of granite, gneiss, and mica-schist, none of which have yet been anywhere identified in situ ; this conglomerate varies from 400 feet to 6 feet thick in the Dingle Promontory, where the whole Upper division of the rocks is 3,000 or 4,000 feet thick. The great mass, extending from the Iveragh Promontory to Killarney (Map G), has been mapped into three divisions, the Glengarriff Grits, the Lower, and the Upper Old Red Sandstone ; as, however, the two first divisions pass into one another laterally the distinction is merely a lithological one. The lowest rocks con- tain green (1010, 1011), red (663), and purple (1007, 8), grits, highly micaceous and conglomeratic ( 1002), with purple (1003, 6) and green (754) slates, which take on different colours under the action of the sea and the weather ; the upper division is thin, and of the usual brown and yellow colours. A set of igneous rocks, iuterbedded and intrusive felsites and ashes, occurs on Valentia Island and in the picturesque mountains about Lough Guitane, near Killarney (v. pp. 91 and 92), while west of that place the Old Red Sandstones rise into the grand heights of the Reeks, the loftiest mountains in Ireland. A number of Du Noyer's drawings illustrate the mountains formed of Old Red Sandstone in Kerry (D 3, 5, 6, 10, 14, 16), and three others (8, 9, 15) give views of sections or mountains where the volcanic group can be seen. The total thickness of Old Red Rocks seems to be not less than 1 3,000 feet. In the Glengarriff Region both Upper and Lower divisions are present, and there are igneous rocks {v. p. 91) in the extreme west and on Dursey Island, while sedimentary rocks of the usual types (880, 1037, 667, 760, 1019, 1020) occur in the extreme Western and Southern parts of Cork. Between the Upper and Lower divisions in the extreme South, green, copper- bearing, sandstones (1278) occur amongst the limestones?, and they are traversed by lodes of copper-pyrites, which have been worked with profit at Alihies, near Berehaven. About Bantry there are veins of barytes in the Old Red slates and grits, and on the south coast of Cork the rocks are banded with beds of grey coj)per ore passing into malachite and azurite. In East Cork and Waterford (Map A) the total thickness varies from 5,000 to 9,000 feet, and the whole series appears to be a conformable one. The Upper Beds have not only yielded fossil plants but also the shell Anodonta Jukesii, whose nearest living relative is the freshwater mussel. This fossil is of great value in indicating the extreme probability of the view that the Old Red Sandstone was formed in great freshwater lakes. The unconformity between the Old Red Sandstone and the Silurian rocks is well ?hown in Du Nojer's di'a>i,'ijig, D 17. 86 MtTNSTER. [cases XXIS.-XXXI. Cases XXIX.-XXXI.— The ' Cabboniferous System. The Carboniferous Slate and Coomhola Grit.^Jn the northern part of the Province this Series is thin, from 150 to 400 feet, and consists of shaZeSy'Jlags, sandstones (678), and hard siliceous ■g'ri< (16,70), with 3, few. limestones in Clare and Limerick. Furtlier South it assumes the characters of the two lithological types, named by "Jukes Carbpniferous, Slates ,afld Coomhola Givits. , These tyyo types gradaate.intQ one another laterally, and cannot he regarded as chronological sub-divisions, although. grit§ are, as a rule, more common in the lower part of the Series. The, rocks thJeken rapidly towards the South as they are brought up i]> the recurring anticlinal^, and become- successively 1,500, 3,0pQ, and even 6^000 feet in .thickness ; indeed, from Crookstown to the -Old Headrof Kinsale,the slate series thickens f]:om.60 to 6,000 feet in 13 miles. There can be little doubt that as the Carboniferous Limestone occupies less and less space in these anticlines, the beds of grit and sandstone to, a large extent replace the lower be.ds.of the liin^tpne, of the North, showing that while a deep sea extended in the Carboniferpus Limestone Eppch over, the ,north of Munster, its southern shore-line was not far scm.^ of Ireland. . , . The prevailing character of the ro.cks is ^s follows : — Olive and black (865) slwdes, and «fa Brachiopoda. ■The Brachiopoda are not at present of muck use in indexing the minor subdivisions of strata, although there is little doubt that they will eventually become very serviceable for that 104 GENERAL PAI^/EONTOLOGT. purpose. They are never compound like the Polyzoa, although Bomewhat similar to that division, in general structure. The animal, whose " mantle " lines the shell which contains it, has a mouth furnished with long, spirally coiled, " arms," which are lined with cilia whose function is to carry food to the mouth. The larger valve contains the greater part of the animal, and is termed the ventral valve, while the other is spoken of as dorsal. The result is that the two valves, being upper and lower in position, are unlike in shape (inequivalve), but as the animal is symmetrical, with its right and left halves alike, each valve is symmetrical (or equilateral). The " beak " or projecting portion of the ventral valve is usually pierced by a hole through which passes the muscular filament by which the animal is attached to stones, shells, or the sea-bed. The interior of the shell is usually provided with some contrivance for supporting the parts of the animal, particularly the complex, food-providing, arms. This support takes many different forms : In Orthis and Ptoducta the thick mass of the valve is sculptured to receive the arms and muscles ; in Meristella there is a process shaped like a shoe-horn; in Pentamerus a number of plates dividing the shell into five nearly closed chambers ; in Spirifera and Atlwjris spiral processes of various forms ; but in Terehratula and other M.esozoic genera there is some modification of the " loop " or " cai-riage-spring apparatus." As a rule the more complex contrivances are found in Palseozoic genera, while the loop occurs in the genera of later rocks. The two principal divisions of the Brachiopods, the Inarticulata (or Tretenterata) and the Articulata (or Clistenterata) are to be found in the Cambrian rocks. In the first division the valves of the shell are not united by a hinge. The Ai-ticulata have a defined hinge. The first division has not varied much in niimbers throughout geological time, the second was very rich in numbers, both of individuals and species in Silurian, Old Red, and Carboniferous time, certain genera were important in the Meso- zoic era, but on the whole the division dwindled down to the present day. MOLLUSCA. This sub-kingdom is in advance of that previously described in that the nervous system is composed of three principal pairs of ganglia united by cords and prolonged into nerves, whilst there is a well developed heart consisting of two or usually three chambers. Eespiration takes place by means of giUs except in terrestrial forms which are provided with a pulmonary sac or lung. The shell is usually external, but sometimes it is in the foiin of an internal skeleton, while at times it is altogether absent ; the organism is never compound. The sub-kingdom is divided into four classes, of which the Lamellibranchiata are head- less, whUe the Gastropoda, Pteropoda, and Cephalopoda possess heads, the last division standing on a higher plaue than th& rest of the sub-kingdom. LAMELLIBRANCHIATA AND GASTROPODA. 105 Lamellibranchiata. The LatnellibraDohiata or Pelecypoda are the lowest class of the Mollusca proper. The body is protected by a shell made of two pieces or valves. The animal usually rests on the beaks of the valves on the sea-bed, so that the valves are not dorsal and ventral as in the Brachiopods, but right and, left in position. In consequence, one valve is the symmetrical counterpart of the other, and the shells are equivalve but not equilateral. The chief points of organization which are of classificatory value are the follow- ing : — The presence or absence of a siphou and its retractile character or otherwise ; the number and relative importance of the adductor muscles, and the consequent marks of their attach- ment to the shell ; the nature of the attachment of the mantle edge to the shell, as indicated in fossil shells by the pallial line impressed on the shell ; such a line is either a simple or an indented cur%'e. The shape and ornamentation of the shell, the presence and number of hinge teeth, the luntile or space behind the beaks, and the hinge area, are other important points to bo observed. The division of Lamellibranchiata makes its appearance in the Cambrian rocks, but very few genera are found there. They gradually increase in number up to the present day, when there is probably a larger number of species than at any pr'evious time. In many cases Palaeozoic genera have become extinct, but most of them have rather close allies in the seas of to-day. The bulk of Mesozoic and Cainozoic genera belong to the Siphonida, and of the Palaeozoic forms to the order of Asiphonida. Gastropoda. This class of the shellfish possesses a distinct head provided with eyes, and is confined within a single shell which is usually a hollow cone coiled on itself in a right-handed spiral, very rarely divided by partitions, and only in certain genera closed by a horny or calcareous door called an opercvlum. The features of classificatory importance chiefly depend on the structure of the soft parts of the animal, some of which, however, influence the shape and character of the shell. The chief fossil forms belong to the order Prosobranchiata, in the modern genera of which the "ills and auricle are in front of the ventricle of the heart. The lip or edge of the shell is entire in. the older forms, indicating that the animals were vegetable feeders, and were not possessed of a siphon for carrying aei-ated water to the gills. The later forpis have often one or more canals, which carry the siphon, at the lip of the shell. These are mostly Carnivorous, but both types survive in great numbers to the present day. The Pulmonata or lung bearing shellfish, to which division the land and freshwater snails belong, have usually a simple shell. The Pteropods or wing-footed shellfish live on the surface of the sea and consequently their remains are found at all depths, while 106; . ' GENERAL PALAEONTOLOGY. ' ; certain deep-sea oozes are largely made of ]^eir remains. The shell is generally a simple cone, and examples of the group are found as early as in Cambrian' iinle. ■'■" ■ • !■• i .■ -n' ;,, ,i, :' v'.f ,!')' The Gastropoda are colnjiaratively rare in ^he lower Palseozoio rocks, but are present in very considerable numbers in the Car- boniferous. They are again verjr charabteristic of the Jurassic and Gretacebiis'i'ocks, while tropical and sub-tropical' genera abound in the Tertiary stnatta. They are perhaps more abundant at the present time than ever. The land and freshwater types haVe varied very little' since Carboniferous times,' but from the nature of tlieir habitat they are not very coinmon as fossils. Cephalopoda. ' This idivissiop stands ^at the head of thp Ifolhisca, but is less frequent in ;the seas of to-day th9,n it has. been in the past. The Cuttlefish, Nautilus, and Argonaut are amongst the. f^w living types, and in them the anima]. possesses a distinct head, with 9. motith surrounded, by tentacles, and two , large , eyes, gene- rally well developed ; in some forms there is an ink bag. The most important fossil genera are refeired.tofthe Tetrabranchiata, repre- sented now by Nautilus, possessing two . pairs qi gills .and enclosed in a chambered shell which is enlarged as , the , animal gro'vys, the hinder part being partitioned; off into chambers. , ,The more important Palaeozoic genera like Orthoceras and ^auPibjks, which came in in Sijurian times, became extinpt or much climinished in. numbers in, ,]^e^oz9^c, timeSj.find; were replaced by enormovis,; numbers i.pfithe ^r&a.% Ammonfite genus ,>^hicjii ip! turn became extinct in the Tertiary rocks after developing many extraordinary modifications in Cretaceous time. The two-gilled order, Dibranchiata, is represented in the Secondary rocks by a greiat abundance of the guards of Belenunites, a genus allied to the modern Sepia, vf\&.ck became extinct at the end lOf, Cretaceous times. .(This order of the. Cephalopoda is the one most frequent in modem tunes, NautUus being the only surviving tqtrabran- chiate form. Vebtebrata. The members of this sub-kingdom have am internal bony skeleton which supports a nervous system composed of brain and spinal chord. They never have more than four Umbs, which are turned towards ' the ventral aspect of the body.- ' • The sub-kingdom is divided into five principal classes, of which the Fish stand lowest and the' Mammals highest in the scale of life. Fish. The oldest known fish occur in the Silurian rocks in which spines and detmal plates belonging to Selachians and Ganoids have been found. In the Selachians, the Dipnoi, and in. the older Ganoids, the inner skeleton is cartilaginous throughput, VERTEBRATA. I07 life, while the outer skin is prot^ted by isolated granules, tubercles, and spines, or by a continuous covering of bony scales. The G-anoids attain their maxiiAum in the Old Red rocks, are fairly represented in the Secondary rocks, but exist only in very smtill numbers at the present day; The niimber of Selachians does not appear to have varied much in past time. The Dipnoi ot niudfishes, the nearest to the amphibians in structure and in the fact, amongst others, that the air sac is modified to' act aS a lung, makfe their appearance in Devonian times, existed in 'great numbers in Triassic time, and then died down until they are all but extinct at the present day. The Teleosteans, or bony fish with a perffeot ititernal bony skeleton, the highest order of the clas^, do riot make their appearance till the Cretaceous Period. ' ' Amphibia. The Amphibia come next in the scale. They breathe by gills in the earlier part of, their lives, but two lungs are always pfesient. in the adult. No amphibians, except these belonging to the Labyrinthodont order, are known from rocks older than Tertiary, but,.ttii^ pr.der is pt great i^upprtan,C9 in the Carboniferous^ Pfermian, and Jurassic Periods. Examples of these will be iloticed under the Upper Carboniferous fossils of Ireland. Beptilia. The animals of this order, which never pass through the early water-living stage of the Athphibians, breathe by luiigs throughout their whole esdstence. Of the ten orders into which the sub- kingdom is divided, no less than six are extinct, and it reachesthe acme of its development in Mesozoic times. It is possible that the earliest reptiles are Carboniferous, but in the Permian strata they undoubtedly occur. In the Mesozoic rocks occiir IchthyosauTSj-Plesiosaurs, Pterodactyles,- Deinosaurs, and Anomo- dontia, and to such rocks their remains are confined ; but the ancestors of existing Ghelonia (Tortoises) and Crocodiles appear also in these rocks. The Ophidians (Snakes) are the only order at present not known to be older than the Tertiary period. Birds. About these the rock record has little to tell, for they are very rarely preserved as fossils. That little, however, is of surp^sing interest, for the Mesozoic forms, thfeSanrurse and the Odontornithes, approach on the' one hand such reptiles as the Pterodactyles, and on the other the Deinosaiirs, in the shape and character of their limbs, brains, or tails, in the possession of true teeth in the jaws, and in the general configuration of the skeleton. No fossil birds older than the Jurassic Period are known, whilst thpse of the Tertiary Era make a much closer approach to those existing at the present day. - — „™. » - . — .- .—. — — — ,~ 108 PALAEONTOLOGY OF IRELAND. Mammalia, This division, to which the ordinary so-called quadrupeds belong, is but rarely found fossil, except in the Tertiary rocks. It is true that a few species have been found at exceptional localities in the Triassic and Jurassic rocks, but the great evolution of the families and genera of the Mammals took place in Tertiary time. It is possible to trace back some of our existing species, and to find links between these species in Pliocene times, links between existing genera in Miocene times, and between what are now entirely separate families in Eocene times. It.is thus possible to work out the actual line of descent of many of our living species from ancestors which , are less specialised and more and more generalised in character the further we go back in Tertiary time. Man, the highest of the Mammals, has left traces of his bones, implements, and dwellings at different periods, hut the earliest of these have not been yet traced back with certainty to any period earlier than Pleistocene, and not indeed to the older part of that period. 2. THE PAI.2!ONTOLOGT OF IRELAND. The Collection of Fossils is arranged in historical (chronological or stratigriiphical,) order, the oldest being placed first at the south end of the gallery and progressively newer forms along the cases towards the north, where the youngest are to be seen. The large labels in each case show the particular geological formation or horizon from which the surrounding specimens have been obtained. The following key will show at a glance the method of arrangement. The numbers refer to the flat table-cases which are placed across the room and in the windows, and to ten cases and a series of ^ec^este^s on the west side of the room, Caso. Systoms and Sorica, 1. Pre-Cambrian ? 2. Cam'brian. 3-9, in part. Lower Silurian, including some Upper Silurian. 9 rest -10. The Portlook Silurian Colleotion. 11-13. Upper Silurian. li, 19, IS, 19. Old Bed Sandstone. 16-26.42,46,48,50. ( Lower Carboniferous Books, and Carboniferous j Limestone. 27-33,38,41,43,44,46,50. Toredale Series to Coal Meamres. 34. Permian, Trias, Bhsetio. 34, 35, 46. Lias. 36,37,46,51,52. Cretaceous. 39. Eocene or Ollgocene. 40, 50, 53. Post-pliocene to Eecent. CASfiS 1 & 1] GAMBElAU FOSSILS, 109 Witliin each of the divisions thus specified the fossils are arranged zoologically, according to their place in the scale of life, the lower forms being placed to the left and the higher towards the right. On the labels at the bottom of each tablet will also bo found the more exact horizon from which a fossil has been obtained, when this can be accurately ascertained or defined. Type- specimens, figured and described in the Survey Memoirs and else- where, are deposited in a special case in the general Palaeon- tological department of the Museum, and the Portloch Types are in the Museum of Practical Geology in London. Case I. —Fossils in Strata associated with Foliated Rocks. In this case have been placed the radiating masses of crystalline carbonate of lime, which display a structure rudely approximating to that of Favosites, Holy sites, Golumnaria, and other Corals. They have been considered by Professor Hull and other observers, since their discovery by Mr. Patrick Ganly in 1856, as belonging to one or other of these genera. Their chief interest is that they occur in rocks of great but unknown age — limestones interbedded with the quartzites and schists of CuldafT, in Donegal. It should be noted, however, that in the magnesian limestone of Durham undoubted, inorganic, radiating, calcite-coucretions occur, which mimic organic forms much more closely than these ; and it is possible that eventually the affinities of the Culdaff forms will be found to lie with them. On the other hand the discovery of possible Radiolaria by Professor Sollas in the same limestones (re- ferred to on page 97) indicates the strong probability that fossils will eventually be found in these rocks. In black slates from the same county, about Pintown, Mr. M'Henry has also found mark- ings, too obscure for generic determination, which look like dis- torted Graptolites, and which, if they really turn out to be graptolites, are likely to indicate that the rocks containing them are of Lower Silurian age, as they appear to belong to tjie DiplograptidcB. Case 2. — Cambrian Fossils. Many years ago a singular organism was found in the Cambrian llocks of Howth and Bray. It was named Oldhamia after Dr. Thomas Oldham, at that time Director of the Geological Survey of Ireland. Much discussion has arisen as to its true nature. It has been referred to various grades in the animal kingdom — a sertularian zoophyte, a graptolite, or a polyzoan ; by some writers it has been considered to be a plant, possibly one of the calcareous sea- weeds, while some have even suggested that it is an inorganic structure possibly connected with the crushing or shrinking of the beds which contain it. It consists of fans of thread-like branches sometimes springing from a central axis at regular intervals. 110 PALEONTOLOGY OF IRELAND. ' [CASES 2-11. I'liree species of this organism, Qldhamia radiata, 0, antiqua, and 0. discret^^ haye bpea distinguishecl, and specimens of them •will-be fpund in case 2. The gi?it rocks in the Irish Cambrian System are frequently- marked ''by burrows attributed to the action bf' worms 6r other anndids. ArenicoUtes consists of: burrows in 'the form of a U, Scolithus forms long, straight, vertical burrows, while ffiMioderma is a curved burrow opening- with a trumpet-shaped month- on the sUrfece of. a small mound. Tracks and what are supposed to be casts of the interior of worms also occilr. -Professor SoUas has recently figured and described under the name of Pucksia •MofiMenryi certain, small, crushed, cylindrical, bodies^ doubtles^s organic, which occur at Pucts Bocks on Howth! The trilobite faunas of the Cambrian rocks have not yet been dis- ccsv^red j,n Ireland ; .tb^i oldest ifeima, is tha,t distinguished by! the pccurrence otfileneUus, ths, second(,(tihe .Hajleph beds in pai-t and theMeneyian series of Wales) hj Ffia-a^Qspides, Agv,o^tt?, , an^ Conocoryphe, the third, (insjluding the ,Lingulfi Flags and Trem^d?ic Slatep) by Ohnus, Asapjiellus, Angelina, Neseuretus, a^nd Niobe, , Cases 3-13. — SiltjEian Fdss];Ls. The fossils shown in cases 3^13 are divided into three sets :— (1) Those from areas mapped by the Survey as Lower Silurian but including probably Upper Sihirian rocks as well ; cases 3-9 ; (2) the Pbrtlock collection from Loiidonderry, Tyrone, and 'IFffltnanagh, aiid a number of other localities which are referred t6, with figures knd' descriptions of type specimens, in the ''Geology of LondondeiTy," cases 9 &' 10 j' (3) those from itndoubted Upptir 'Silurian areas, cases 11-13. Beginning in case 3 with Plants and Graptolites the scale ' bf life rises until case 10 with its Cephalopoda is reached. The Plants are very imperfect aJid may be merely fucoidal "iiVarkiii^s ; they are froni Tipperary. ' A doubtful Sponge' ffom the black shale of Waterford is also exhibited in this case. The Graptolites give evidence that the Silurian rocks of the country may be split up ;into smaller ^divj.si,ons,tJian are recognised at present. Indeed the" work done by Lapworth and Swanston has already (borne fruit and , the. zones recognised by them are now Jaeing fpllowed and mapped by the officers cjf the Survey , towards the squtb-west. The Qraptplite^jfrom the Arenig Spries are highly , ccenosarc. The .primary bran(^h divide^, iintp two, each, of th^se into two more, and so qn until a single colpny may contain hnndreds of branches.. This is ,,j;he,case with DicJiograpttis, Tetr(igraptv,s, anA,,Ijpganqgvaptus. Qiccasipnal forms occur which consist of twp single pens joined ^gether to form a f double pen" as in Diplograptus, but thw genus CASES 3-11.] . SILURIAN FOSSILS. Ill is iiat common ia such early rocks. A more eomhion Arenig fo!Fm is Fhyllograptus which, has four such " pens" united " back tw back." , ;i : 1 .' >l ;';"■.->■■'■': The branching is not Carried so far in Upper Ar^nigi andi liowef Llimdeilo rocks, where singly branched farms like ^idyniogrdptus and Diedlograptus are met with; Thus Didyrtiogmptus Murchisom, occurring at Belle wstbwn with Diphgiriiptug: foUacms, indicates a Lower Llandeilo age for these beds.' The higher Llandeilo or Lower Bala beds are characterized by the slender .graptolites ieptograptus and Goenograptus. Glimacograptus , bicomi^, ■Gcenograptv^ gracilis, Didymograptus Sisingeri, Dicrcmdgre^tttSB ramosus, Diedlograptus 'sextans, and Leptograptus Jla6eidug,i}iaiyB been obtained from the Ball ygrot beds of Down, from Tramore at Gibbet Hill, and the river Suir in Waterford, Ball^more iind Goref in Wexford, Six^mUe-bridge and Belvoir in Clare. The Bala beds at Oarnalea and near Saintfield in Down, near Poylntz- pasS in Armagh, and near Slane in Meath, have yielded Glimaco- graptus 'bicomis, G. Scharenbtrgi, Gryptograptus Pricornis, Micel- logra/ptus Forchliammeri D. mojffhtensis, Dicranograptus Glingani, ^iplograptus perexcavatus, and D. truncatus. The Llandovery rocks are marked by the appearance of Monograptidse, such as Monograptus, Cyrtograptus, and Eastrltes and the gradual diminution of the Diplograptidse. The Llan- dovery rocks of Coalpit Bay' contain Glimaobgraptua normedis, Dintotphograptvs Swanstoni, Monograptus gregarius, jRastrites perBgriuus, and Hetiolites perlatus. Similar forms occur near Dromore in Down, near JPpyntzpass in Armagh, and E.. p.nd 'S.E. of Slane in Meath. , .. ; . , ■ Somevsrhat higher beds are indicated at Tieyeshijly, Eqmecoy, and Lisbellaw by such species as Monograptus Hisingeri^ M. priodon, M. riccartonensis, and if. turrieulatus ; while] strata with a Tarannon fauna occur at Hillsborough and elsewlxevei in Down, and at Salterstow;n in Louth. , ; f,i- ' iiBeds containing ^ Monograptus priodon ^pd M. Sedgwicki occur near Balbriggan an4 on Lambay^ while GyrtograptUB,\a,vsSi M. jiriodon are found at several places in Clare and Tippeirfiry, proving that Upper Silurian (Tarannon or Wenlock) rocks rest on the Lower SUurian rocks there, riue specimens of, M. priodon from JSarnane' ifill in Tipperjiry occur perfectly uncriished in a dark grey limestone, while one specimen o vet afoot fong Ws obtaihecj from Goftbrigane iq. the same county. ' ' 'Specimens of most of the fCrms mentioned will be found in cases 3, 4, £i, and '-i ,■ < 1 . , ■■ .' 11. , ^ • ' ■ ■ ' __ ;;; ./'.^ ; The Corals are repre^entefl by such genera aa ffaly sites,, aj^d Heliolites belonging to the Alcyonaria, Favosites to, the Perforata, . Gyaihophyllwm, AcervvJff,xia,i Omphyma, Fetraia, smd ^aphre^iis to the Rugose division, J they hi<.ve been found inDijblin, Kilda^, and W£tterfRp(i;> ■ , , The subdivisions indicated by. the Graptolite faunas are borfie out by the Trilobites where they happen to occur' in th©isame or 112 ^ALvEOKTOLOGY DP IRELAND. [CASES 3-11. in interbedded rocks. These have, however, not yet been worked out with sufficient minuteness to indicate the minor Series and Stages, but only to show in a rough way that the rocks of any particular locality are Lower or Upper Silurian. Thus the species of Asaphus, Ogygia, Ampyx, Illcenus, and Trinucleus, from Water- ford concur with the Graptolites in indicating that the rocks there are of Llandeilo age and the same is probably true of the fossils from Euniscorthy. Species of SpJiterexochus, Illcenus, Lichas, Gheirurus, and Cythere from Kildare are equally emjihatic in pronouncing the rocks there to belong to the Bala series of the Lower Silurian System ; while the fossils from Meath, Balbriggan, and Portraine indicate that rocks of the same age occur in those areas. Specimens of these and other forms will be found in cases 5, 6, and 9. On the other hand, the Trilobites from localities in Dingle, Clare, and Tipperary, in case 11, including Acidaspis, Calymene Blumen- hachi, Proetus lati/rons, Phacops caudatus, Encrimi/rus punctafus, Lichas anglicus, Leperditia suhrecta, seem to show that the rocks here are of Upper Sihirian age, particularly as they are associated with Pentamerus Knightii, P. galeatus, Ehynchonella Wilsoni, Ji. llandoveriana, and Spirifera bijugosa. The Silurian Echinoderms include Palceaster Kinahani and P. ramsayensis, from the rocks of the Bannow coast in Wexford (case 6), where the apparently interbedded rocks have yielded specimens of Oldhamia. Heads and stems of Actinocrinus, and Cystideans like Echinosphcerites are also placed in the same case. Polyzoa and BracMopoda are placed in case 7, many of the latter having been obtained from the Chair of Kildare and the shore at Portraine. The latter include Orthis, Strophomena, Poramhonites, Siphonotreta, Atrypd, Zeptcena, Lingula, Obolella, and Discina ; other Brachiopoda, chiefly Lower Sihirian, are placed in case 8, followed by Fteropoda, including Theca and Conularia from Dublin, Meath, Waterford, &c., Heteropoda, Bellerophon pertur- batus, from Wexford and Waterford, and Gastropods from the Kildare limestone and from Wexford and Tipperary, including Acroculia, Euomphcdus, Paphistoma, Solopea, Turbo, MurcMs- onia. Patella, and Cyclonema. In case 9 are placed the Lower Silurian Cephalopoda, Orthoceras, Cyrtoceras, and Lituites from Dublin, Kildare, Wexford, Water- ford, and Tipperary, fucoidal markings and annelid tracks from Tipperary, and the problematical Nidulites from various localities. The rest of the case, and the whole of case 10, contains the Port- lock collection, with the exception of the forms figured arid described in the " Geology of Londonderry." Fossils from those areas definitely recognised as Upper Silurian have been arranged in case 11. The Graptolites from Dingle in Kerry, supplemented by others from Galway, Clare, and Tipperary, are chiefly single pen (or monoprionidian) forms, including Cyrtograptus and Monograptus. A beautiful set of Corals from the same localities, comprises i'eiraio, Oyathophyllum, Favosites, OASES S-l3,45,& 49.] OLD RED SAUfDStONE EOSSILS. 113 Zaphrentis, JSeliolites, Ualysites, Syringopwa, Aulopora, Sieno- jiora, Nebulipora, and Ortvphyma. The Echinodermata include Aotinocrinus, Cyathocrinits, and Glyptocrinus, and the Trilobites, Acidaspis, Calymene, Proetus, Encrinurus, and Lichas. Annelides and Polyzoa are in the same case. Brachiopods fill case 12, including the following important genera — Lingula, Pentamerus, Orthis, RhynchoneUa, Spirifera, Leptama, Athyris, Ghonetes, Atrypa, and Strophomena. Case 13 contains MoUusca, comprising — Avicula, Pterinea, Oardiola, Grammysia, Orihonota, Cucvllella, Modiolopsis amongst the Lamellibranchs, a few species of Heteropods and Pteropods, seTeral genera of Gastropods, Trochus, Turbo, Looconema, Murchi- sonia, JEuomphahts, Acroculia, and a collection of Cephalopods, including Orthoceras, chiefly from Kerry, Gal way, and Tipperary Case 14-15, 45 and 49.— Old Red Sandstone Fossils. These rocks in Ireland, as well as in England and Scotland, are singularly barren in organic remains, those which have been found being the relics of land and water vegetation or such shells, Crustacea, and fish, as lived in freshwater lakes. From this it is argued that the rocks were deposited in great lakes. Lower Old Red Sandstone. — In the left hand side of case 14 there are a few specimens of fossils found in the pebbles which make up the Parkmore conglomerate of Kerry, a band in the Lower Old Red Sandstone or Dingle beds of that locality. They have been almost certainly derived from the denudation of some Silurian rocks, possibly of Llandovery or Wenlock age. They are Orthis elegantula, Cyathophyllum truncatum, and Crinoid joints. Upper Old Red Sandstone. — Therest of case 14, and the whole of 15, are occupied by a fine collection of plant remains from the well-known quarry at Kiltorcan HiU, near Ballyhale railway station in Co. Kilkenny. It comprises specimens of the beautiful fern Palceopteris hibernicus, and also the cryptogam Knorria bailyana, of which portions of the root, stem, and spore cones are represented. Large specimens of this species, with Cyclostigma kUtorkense, Anodonta Jukesii, and Coccosteus will be found in cases 45 and 49. There are also a few plant remains from Cork and Waterford. In addition to two specimeBS of Paleeopteris hibernicus at the left hand end of caae 15 (see also 45), this case contains a collection of Fish remains, chiefly the bony head- plates of Coccosteus and other genera, and examples of freshwater Cfustacea, such as Pterygotus hibernicus, Limuloides kiltorkense, and Proricaris M'Henrici. A fossil of much interest is Anodonta Jivkesii, related to the modern freshwater mussel, which suggests the probable mode of formation of the deposit containing it. All these specimens are from Kiltorcan. (See also frame 45). H 114 PALAEONTOLOGY OF ffiELAND. [CASES 16-27,42 ■ 50. Cases 16-19 — Lowek Cauboniferous Fossils. „ ^Tiie.:LpTf^er Carboniferous Sandstpiiesand their associated shales .an4;?iW^i'°'i^^v^'^^ in places richly fossiliferous, the rema,ins being generally of shallow^ water, marine, forms, marking the first advance of. the sea which was to spread so widely over Ireland, and give rise to the thick and wide-spread, Carboniferous Limestone Series. Case 16 contains plant remains from the Coomhola grits and Car- boniferous Slate of South Ireland, and some from the Carboni- ferous, Sandstone Serie^;of Antrim and Galway. Crustacea are represented by Ostracods, such as Leperditia, Trilobites, in- cluding^ FhiUipsia pustulcita, and the remarkable Phyllopod pit/iy^QCOfis Golei. Numerous Polyzoa occur in this series, and tiie 1 rest of this case and a considerable portion of the next (17), are occupied by the abundant Brachiopoda, several genera of which, such as Spirifera and Producta, are of great iniportance in the Carboniferous rocks. Orthis, Chonetes, and Meris^lja are dying out, but Tfire]bratula_ and Rhynchonella for the first time become common and important. Ijamelli- brancliiata of many genera fill up the rest of this case and part of the^ npxt (18), which is taken up with Qrastropods, anibngst which are specimens of Euomphalus, Natica, Plmrotoniaria, Loxonema, and Acroculia. Pteropods, Conularia from Hook Head in Wexford, and Cephalopods, OfiAoceyaSjfxOwmiiies, and Nautilus from Cork,- Tyrone, and Fermanagh,: Case l9 contains a 'set of Sliells and Cry^tbgamous Plants from the Lower Carboniferous Sandstone of Ballycastle in Co. Aiitrim. The following are the chief genera represented in this collection : — Sphenopteris, Alethopteris-, Feeopteris. ' Case 27 contains, ini the left hand side, a collection of Lower Coal Measure Brachiopods, including Rhynchonella, Spirifera, Producta, -Orthoceras, and Athyris ; Lamellibranclis. — Aviculo- pecien^ ^dmondia, and Posidqnomya ; a Cephalopod — Nautilus, and one example of ,a Trilobite, Phillipsia; alsp .fragmen^ts of Echinoderms — Actinocrinus and MJiodocrinus. Cases 20-27, 42, 46, 48, 50. — Caebonifeeotjs Limestone Fossils. This diyisipn not only spreads out over a vast area in the country, but is distinguished by its great thickness, and the abundance, variety, and admirable state of preservation' of its fossils. The first case X^Q) contains a few specimens of Cryptogamous Plants from the sandy deposit^ of Wexford, followed by an excellent collection of Corals from several localities, the chief of which are situated in Limerick and Wexford. At Hook Head, in Wexford, the rocks are lying almost horizontally, and, being exposed to the action of weather along the sea-coast, the fossils stand out in relief on the surface of the beds, and can be obtained in such quantity that the locality is perhaips the best in Ireland for fossils of this age. CASE'S 30-27,42-30.] carboniferous limestone fossils. 115 The corals are for ike most part of reef-buildiug kinds, and many of them are crowded together in the position of growth, thus suggesting t^iat aa old coral reef is here exposed to view. The following are the more common genera : — Lithostrotion (saYevail species), (pedestal 48), Cyathophyllum, Amplexus, Michelinia, Syringopora, Zapbrcntia, Ghaitetes {v. cases 20, 46, 48, 50); Corals are followed by Echinoderms, of which, again, this limestone fur- nishes a profusion (case 21) ; indeed, some portions of it are actually made up of broken bits of the stems of orinoids, which, however, are rarely found sufficiently perfect to warrant specific identifi-cation. Where the head of the " sea lily " is preserved, as in nuTuerous cases displayed here, identification is easy, and the following genera are peculiarly abundant : — Actinocrinus, Plaiy- crinus, Poteriocrinus, Palxchinus, Archoeocidaris {Homotmchus), and P^ntremites. The rest of the case is taken up with some fine exataples, of Annejides. Thie beginning of case 22 is taken up with Trilobites, thalast survivors of this order known in Britaiai. There are but four genera left, Griffithides, Phillipsia, Proetus, Braahymetopus, which, iave been obtained from localities in counties Donegal, TjTone, Dublin, Kildare, Limerick, and Wexford. Polyzoarare plentifully represented in this case, which also contains an im- portant series of BracMopods, continued in cases 23 and 24, and including the following abundant genera : — Producta, Spirifera, Chonetes, Meriatella, Athyris, Rucleospira, Discina, Orthis, Lingula, Terehratula, Ehynchondla, and ■Streptorhynchus. Amongst the Lamellibranclis, which are placed in case 25, the following genera are confined to the Carboniferous system ; — Edmondia, CardiomorpJia, Sanguinolites, and Pleurbrhynchus ; but manyother genera are of great abundance and importance, asfor instance :_ — -Avictdopecten,. Aviaula, Pinna, Inocerfomus, Posido- nomya, AspinuSji&TidModiola. . A few Heteropbds — Bellerophon — of several species, fill up the remainder of this case. . ' The left liand two-thirds of case 26 is taken up witW the collection- of G-astropods, including such gen«ra as Mm-^ chisonia, Macrocheilus, Euomphcdus, Pleurotomaria, Naiicd, Loxonemd, Platyscldsma, Acroculia, Phanerotinus (case 50) and several othei- genera for the most part extinct at the present day, 'or\stibgenera presentins; many points of difference from their nearest ' Uving relatives. The Gastropods are followed by the Cephalopods, such as Nautilus, Orthoceras (pedestal 42), PiloceraS, Temnocheilus, Cyrtoceras, Goniphoceras; pi sxicii Palseozoic types as these the Carboniferous Limestone Epoch witnessed the last grand development, while Gonicctites marks the incoming of fotins belonging to the Ammonite type which was to be pre- dominant in the Mesozoie Period. Most of these specimens, and others which occupy part of case 27, are from localities- in Lim- erick, but the rest have been obtained from Dublin, Derry, Tyrone, &c. -This case concludes with specimens of teeth, and palates of manTgeiiera of Pish, chieHy belonging to the- order of Elasmo- H ^ 116 PAL^OOTOLOGV OP mtiLAND. [cASfeS 27-SS, 4l-50: branclis, to whicli the existing Sharks, Rays, and Dogfishes belong. The following genera are of importaiice : — Gladodus, Cochliodus, Oyrctcamthus, Eelodnis, Orodtis, Petalodus, Psammodus, PsephoduB ; PalceonisciiB belongs to the Ganoids. Cases 28-33, 38, 41, 43, 44, 46, 50.— Lower Carboniferous AND Coal Measure Fossils. Case 28 contains fossils from Coal-bearing rocks which afe situated below the level of the Coal Measures proper ; the beds called the Shale and Flagstone Series, which correspond in position with the Yoredale Be4s and Millstone Grit of the English coalfields. Specimens of fossil plants from these beds in the Leinster and Tip- perary fields are also placed here, and some from other fields, as well as Brachiopods and LamelUbranchs from Dublin and Meath. Fish from the same area are shown in case 28 ; the remains con- sist of bones, teeth, and scales — the best examples being derived from localities in Cork and Kerry, whence come the entire skele- tons of Coelacanthus and portions of Holoptychius. Fossils from the true Coal Measures are placed in the set of cases beginning with 29, which, with part of 30 and 60, is devoted to plants. The following are characteristic and well-preserved plants -.—Lepidodendron, Sigillaria, and Stigmaria, whose nearest living analogues are the Lycopods or club-mosses, Galamiies now represented only by dwarf specimens of Equisetums or Horsetails ; herbaceous ferns and tree-ferns such as Aster ophyllites, and coni- ferous trees. The Lowest Coal Measures frequently contain marine fossils (•30), which are related to those found in the Carboniferous Lime- stone. Such are the Folyzoa Fenestella, Cladochonus, Glcmconome ; the Echinoderms Aetinocrimis, Cyatlwcrinus ; and the Crustacea Belinwrus, of which three species are shown. These fossils have been obtained from Dublin, Limerick, and Queen's County. The thinly represented Brachiopods of these beds are to the left hand in case 31, and include Lingula, Producta, Spirifera, Athyris, Rhynchmiella, and Chonetes, followed by a large number of Lamellibranchs, amongst which the following genera seem to be confined to marine areas — Myacites, iMnulicardium, Myalina, Aodnus, Edmondia, Aviculopecten, Posidonomya, while Unio and Anthracosia inhabited fresh water and some few genera lived in brackish, fresh, or salt water indiflTerently. A few tracks attributed to Mollusca are shown in the pedestals and cases 43, 44, 46. Case 32 contains Cephalopods, Goniatifes, Nautilus, and Ortho- ceras ; Heteropods, Seller option ; and Gastropods, Loxonema, Murchisonia, and Macrocheilus, from various Coal Measures throughout the country, with a small collection from Derry and Limerick. A fine collection of fossil Fish from Jarrow Colliery in Kil- kenny is placed in case 33. Some of the specimens are entire skeletons, referred to Goelacanthus and Rhizodus, while some are .CASES 34, PERMIAN, TKIASSIC, AND MASSIC FOSSILS. 117 35, & 38.] undescribed species, which are probably new. The remains of a small fish, probably Amhlypterus, will be found in case 38. This case also contains a number of Labyrinthodont skeletons from Jarrow, amongst which an almost perfect skeleton of Urocor- dylus Wandesfm-di is conspicuous ; Ophiderpeton Brownriggi is also represented. The larger of these forms probably measured 7 or 8 feet in length, but many of them were very much smaller. In case 41 are other remains of Labyrinthodonts including the heads of Loxomma Almanni, Ichthyerpeton Bradleyce, and Anth- racosaurus Russelli, and the almost complete skeletons of Kerater- peton Galvani ; the specimen of this last species described by Professor Huxley, together with type specimens of Fish, Amphibia and other Coal Measure fossils are removed to the special collection of type fossils placed in the Palaeontological room in the annexe. Case 34. — Permian Fossils. The comparatively few fossils which have been collected from the Irish Permian rocks are placed in the front part of case 34. They comprise the Coral Favosites, Polyzoa, BracMopoda, such as Producia horrida, Lamellibranchs, Uke Bakewellia, Mytilus, Schizodus, and the Oastrppods, Turbo and Rissoa, most of which are stunted and dwarfed by the unfavourable conditions under which they lived, while they are poor in numbers both of individuals and species. Case 34. — Triassic Fossils. The Triassic fossils are also very scarce and comprise a few relics of Plants, Equisetites and Lepidostrohus (1), Crustacea mostly such as lived in lakes like Estheria, and Fish, several perfect specimens of Dictyopyge (Palceoniscus) catoptera. Case 34. — RHiETic Fossils. The Rhsetic fossils in the same case are such as lived in brackish water, and indicate that the sea was finding its way into the Triassic lakes and lagoons. The fossils are fairly plentiful but do not present any great number of species, the most abundant being such forms as Gardium rhceticum, Avieula, Astarte, and Fecten valoniensis. In addition to Lamellibranclis, scales of Fish are abundant, amongst the genera being Gyrolepis and Acrodus. All these fossils come from the North of Ireland, chiefly from Antrim, Derry, Down, and Tyrone, where alone these and the succeeding Mesozoic rocks occur. Cases 34 and 35. — LiAssic Fossils The right-hand portion of case 34 and the whole of 35 contains fossils from the Lower Lias of the north of the country. The following zones appear to be represented, those of Amnionites 118 PALEONTOLOGY OF lEELANO. [CASES 35-37. planorhie, A. angulatus, A. Bucklandi, and possibly A margari- tatus. Corals are represented by Montlivaltia, Echinodenns by Pentacrinus, Hemipedina, and Diadema, Annelides by Serpula Icevis, and Brachiopods by Lingtda and Terebratvla. The Lamel- libranchs include Lima, Pecten, Inoceramus, Pinna, Madiola, Hippopodium,' Unica/rdium, CucuUcea, Gardinia, Myacites, Pano- fma, and Goniomya, the Gastropods, Turritella, Pleurotomaria, and CAemmfem, and the Cephalopods ch.K&j Ammonites like ■A. intermedius, A. planorbis, A. Johnstoni (v. case 46), and Bekrrir nites such as B. aeiiius and B. ahbreviatus. Case 36. — " Upper Geeensand " Fossils. • The Upper Cretaceous Rocks of Ireland are only represented by a thin band of so-called Greensand followed by the Chalk. The former is probably the equivalent of some of the zones of the Lower and Middle Chalk of England, and the latter of part of the Upper Chalk, including the zone of Belemnitella mucronata. The greater depths of the Chalk sea do not appear to have spread so far west as Ireland until towards the end of the Epoch, so that the deposits are of an abnormal character. The " Greensand" fossils include Annelides (Serpula), Corals, Parasmilia, Brachiopods, Ter'ehratula and Rhynchonella, Lamellibranchs, Pecten^ Spondylus, Exogyra, Inoceramus, GrypluBd, and Fish, Lamna, Ptycliodus, and Otodus. These fossils were obtained from those localities where portions of the " Greensand " crop out from under the Chalk escarpment as at Belfast and from Carrickfergus to Lame ; many of them were collected by Portlock. Cases 36 and 37. — Chalk Fossils. . ^ , This collection includes many which originally formed part of that of Portlock, but a large number of species have since been added to it. The right-hand side of 36 contains the following, among other fossils :— Sponges and Corals, Ventriculites, Scypfna, Coscinopora, Cliona-, and Paramondras (case 53) ; EcMnoderms, Echinocorys, Cidaris, Cardiaster, Holanter, and Echinoconus ; Brachiopods, Terehratida and Rhynchonella. In .Case 37 the following are represented :— Lamellibranchs, Astarte, Gardinia, Gryphcea, Inoceramus, Lima, Ostrea, Pecten, P/Mladomya,ei,iidSpondi/lus;G&stio'pods,Pleurotomaria,Gerithium, AnATu^lo; Cephalopods, JVautihis, Ammonites (v. case5l), BacuUtes, And Bfflemnites. ■ The right-hand end of the case contains a few fossils from a peculiar fragmental deposit which occurs between the Chalk and the Tertiary Basalt on the coast near Ballycastle. Unfortunately the state of preservation of these fossils is not all that could be desired, as the nature and age of the de])osit are unique in Britain. They include Annelides and Echinodermata — Ciddri'a and CASES 39 & 40.] EOCENE AND PLEISTOCENE FOSSILS. 119 Pseudodiadema ; Brachiopods — Terebratula, Crania, and Magas; and Lamellibranchs, such as Pecten quinqtiecostatus ; but it is more than probable the greater portion of them are merely the rolled relics of forms originally in situ in the higher beds of the Chalk. Case 39.— Eocene Fossils. Case 39 contains a collection of plant-remains from old soils, clays, and other deposits about the horizon of the pisolitic iron ores, which intervene between the Upper and Lower Basalts, especially at Glenarm and Ballypalidy. A large flora is disclosed by these deposits, comprising: — Euocdyptus, Pinus, Quercus, Cupressites, Sequoia, MacClintochia, Platanus, Rhanmus, Alnus, Andromeda, and plants of a reed-like character. These fossils are of great importance, as they give the only means of determining the approx- imate age of the Basalt flows. Mr. Starkie Gardner inclines to place the plant beds on the same horizon as the Bagshot beds of the Eocene of Southern England. Specimens of lignite from similar beds at Ballintoy, and silicified wood from various places in Antrim and Tyrone, probably of about the same age, are placed in the same dase and in case 50. Case 40. — Pleistocene Fossils. Case 40 contains marine shells from gravels (" manure gravels ") beneath the Boulder-clay of Wexford and from the sands and gravels in county Dublin. Among the principal species are the following, those marked thus * being extinct ; thus f of northern habitat ; and thus § of southern habitat at the present time : — Fnsus antiquus, Fiisus islandicus, *F. menapii, §F. prostratus, *.N'assa reticosa, ^Natica affinis, *Pleurotoma kevis, jP. exaratd, fScalaria grmnlandica, ^Turritella incrassaia, '\Astarie horcalis, Cyprina islandica, ^Pectunculus pilosus, Pholas crispata. The raised beaches of Lough Lame and Belfast Lough yield also marine shells, most of which still survive. This case also contains Lignite from the pipe-clay deposits of Tipperary, Turritella terehra from the Boulder-olay of Dungiven, leaves and hazel-nuts, &c., from peat bogs in King's County, coral- line-sand from Bantry Bay, and worked flints of human origin and neolithic type from gravels, supposed to be of the same age as the raised beaches, at Larne in Antrim. Remains of Pleistocene Mammals are far less common in Ireland than in England, but the Mammoth, Reindeer, Horse, Bear, and other forms have been met with in the Shandon Cave, Waterford. Skeletons of the great "Irish Elk" {Megdoeros hibernicus) have been found abundantly in the marls below the peat-bogs. Specimens will be seen in the Palseontological Gallery. 120 TYPE SPECIMENS. o H u a> cS 60 O ^ ^ O So 5 _d H -tT TS 01 o 1 1 1 h ■k« s r^ o -3 1 •iH . 05 o -+3 (0 rS 5 £ [2 •m ns a H g H u H 1 .2" 02 ti , eS" 5? ut ■s 00 ft M •3 s ■5 ^ <« •SS3 1 iiN CO S« ^ So, g r •pT eo » > ,.i ^ •^ 3. g> « « N d of M ^ 02 (pl ^' k« 05 ^ P. » p ^ a p. li ra « d •*0S'0 3 »-"Pl CMS IMP IN hiR Pl^v '^ M.^- gs so H- 3| g ^•s .a - «?!, 1 H a "IS «= «- g s a^isl 'f.g -'& z^ 4J00 ^ rH "^ •-l430a"CG ^"-1 ^^1'-' ^, '^M^ '^t '^^ '^1 - §^-^SO so gCJ go ST ari a^ a^ a^ g^ g m 2 w ^.a ■a fc " « r5 y a 51 s^ ,6' ci .3 §8 B H Eh Eh H izi iz; S5 !z; J5 tS«i t>r So6 ri §8S m S ^ $ HU Q Wq z 122 TYPE SPECIMENS. ■a H — Q o m O o •S 1 EH $ if J n bo h A cd d . O c3 m Eh O W P. I 9 a S a D s S o CO W I— I Q E^ CQ CM ni- M pt 5 ^-■^ « w ttfl « ««• •a r (i ■^1 ft J?; ^^ £j S • |s. ■ • • 60 3 bb .si"- db '0 fe> § o a a a p p CJ n K| fe ■ C3 M Is -ft tS§ !§ IS s I a P.I o o Si h; ^ S I .22 o t« t«p OLD BED SANDSTONE AND CARBONIFEROUS TYPES. ] 23 o H Q 03 PI w o o I 3 I s* ss-S •SS 3i? s 6 d5" on 5533 M r "a MS .rf"^- .S*^ fe^ "= Ho &10 Wo & tn o c P^ 02 t3 o Pi Pa S O m a ■"5 I ^ :a pi a .3 - 02 .a S 0^ M 1 i s 2 S g - • ..4 . 00 i-T ' Pi ■ K^'S-.^: w 2 ^ P-S bo a" "w'l a^; " pi OPQ to© 00 COgi-. ■a ? g 1 « H P s •a I S9 02 P4 p-l H Q P5 O I 00 ^ 22 PS- r ^ IN a of oj Pi d OS ■3 CO , -3 8 ^ n s & ,§ s m o •-"«!"«>" ooO-l ift N'^ oS'^ oB— aa'^ K^ -! 'bo .9 a M ^ ^" ri t>. 3 o n Fi4 S3 ™ R s ■^, H o t3 |3 S <3 f I a 5 So, H „ «j' t- of o" -wT IS t- Oj K tjj bb bb w bb bb bb fii 1 a' Sf of fl 2 ?s « a a a I s. a fh S " # I '3 a S s p. s p ,3 =* M ate; s 5 ^ ^ 5 8 4 6 -415 'J S^o ^ § 2 fc g So S© 00 S w SJ N S M eS w «S i rn CO OQ 00 t~ CO fn'o M Mo d d ti d (3 do do do Mo d do 12G TYPE SPECIMENS. s s g w m .a d ■s"- 1 £ 1 ce '3 o o 5 r^ <» i o p ■g n 1 1 i g 1 t3 - A a i d - ■ 1 ; 1- H _0Q ,5 1 o 1^ t-s '- 03 m » 1 jl (§ a 6, g i 85 1 oa 1 g i g ^1 t^ =§2 1 o o ^N* rSoi ti . tn Fh . • 15 ^«^ gj • • • oi 12; IS S'a 1" ^s 2 lO -m- i-^ siS .a- S 0- .^» % n tb «i u bb i . ^ -tieo o-rf ^1 -tS-e^ ■.crt o 1 II si II .P. J -ft (i- CO C- SB' ,■§ ■go 4 ^ 1 g ■ s 1 1^ 1? i| % i 1 W^ 1:3 rl 4 O 59 o " O S cT " WS &:| ^s ^:2 g . » . ^ r , . ■ .fl .J= a ^^ ti M w a i >; .• ^ M s 5' §■ •3 . s o ?s ^" - i a 5,. ,: '^ !^ ■; g g 1 J j: i" ^ 1^ 1 ■i s r .^ 1 a Si is 1 S d^ & ?i 3 .S 1 a ■8 1 1 -1 1; ?^ 1, 1, 1 ^ 1 1^- . 1 ti tn ■ 1 i 1 ■ 1 1 • f — . — , ■ . . — — . — . 1 •B:?,. J. S §1; Cs-ffi-sV5 --a «-s <30 ^■ ^'- i! ■ (§ : « f i do p4o . . • p CAUBONllj'EROUS AND: EOCElsrE TYPES 127 i a 4 1 3 1 g ■^ 1-9 ^. . H M In w M bb&b «« « P.P< a 2 i B'^ " „- =p of P. 4 ' ■ H £■ i 03 t^ W m • ' 1 "S S tS •g w 3 > • • s ,s " ■3 S •g '^- a *.. g •« ■a ^ .?s " =0 s ■S ^ 1 g ■■ff ''I' §■ s" « ft ^ ^ § ^ 1 -« s, ^ ^ . ,;*t ^ ^ B : ■ 1 6H EH ti- 1 ■ 1 . ^— '-0 •" ^ ■a ■ S p. ■a ^ • CO ^ « (i CO p. IS p, M ^ g :g hji ■i g 'HgW > o-Sa 6 & -A ? SHE: s ►^ 03 QC03 . OS t-s 1^ 1 1 1 s «^-~" .1 a :S ;p~ li il |l ^1 3 S5 -It II ^0 H Hi H &^ ■~~' ' !UJ ^ «;®" N IM M f^pi hi H 128 *!!£ ItLtrSTEATIOifg. PART IV. THE ILLUSTEATIONS. Tliese comprise the following classes : — 1. A series of 41 drawings by the late G. V. Du Noyer, placed on the west side and two ends of the room ; a few drawings by W. H. Baily are placed in this series. 2, A set of 5 enlarged photographs of views in Antrim, taken and presented by Dr. Tempest Anderson, placed between the windows on the east side of the gallery. 3. A set of 44 photographs, kindly presented by the Belfast Naturalists' Field Club, and collected by Miss M. K. Andrews ; the photo- graphs were taken by Miss Andrews, Miss Tate, Mr. R. Welch, and Mr. J. J. Stelfox. 4. A set of 47 photographs illustrating the geology of Ulster, taken and presented by Mr. R. Welch. 5. Geological maps, on the one inch scale as issued by the Geological Survey, to illustrate the rocks displayed in the wall- cases. 6. Horizontal and vertical sections of the rocks and mining plans and sections. 7. Small drawings in the wall cases. With the exception of the last three, these are numbered in a continuous series from the south end of the room by the west to the north and east. Deawings and Photographs. Structural Phenomena. — " Dead Cow CliiF " in Kerry (3) shows contorted and faulted rocks of Old Red Sandstone age. The Peak in Magillicuddy's Reeks (16) is an excellent example of the way in which the contortion and cleavage of rock masses affect the type of mountain peaks carved out of them ; 5, 19, 22, and 46 illustrate contortion still further, one example (22) being taken from a locality near Rush in Dublin. Ancient dykes of felsite in the Old Red Sandstone and associated volcanic rocks are shown in 8 and 9, and the familiar section at Killiney showing the granite intruding into Silurian schists is depicted in 21. An admirable example of the uncoriformable relationship of the Old Bed Sandstone to Silurian rocks occurs at Waterford, and is shown in 17. The chert layers or nodules which are so frequently to be seen in the Carbonifei'ous Limestone are drawn in 7, 20, 33, and 47, the first of this set being contorted. The rocks of the Basalt plateaux lend themselves readily to pictorial illustration. General sectiians showing the basalt overlying the chalk, sometimes with a flint gmvel between, and itself overlain by gravel or boulder-clay, will be seen in 13, 23, 24, 27, and 32, and in the jAotographs 59, 69, 80, and 83 ; 83 also iUu.strates the formation of landslips when the heavy basalt is undermined by springs dissolving or soaking the soluble or soft rocks underneath. The bands of iron-ore between the basalt sheets are shown in 48, at Kilwaughter, where the ore has been mined. 28, 29, 43, and 44, and the photographs 58, 60, 68, BRaWiUgs, photographs, and maps. 129 77, 89, and 90, illustrate dykes of basalt penetrating various strata, including Trias, Greensand, Chalk, and Basalt ; some of these dykes show the columns at right angles to the edge of the dyke (77). "Necks" of basalt, the site of old volcanoes, are illustrated by 71 and 74, while 63 shows the great in- trusive sUl or laccolite of Pair Head which is injected into Car- boniferous rocks. Many of those just mentioned, as well as 25, 29, 31, 32, 52, 53, 56, 61, 64, 67, and 72, show the columnar or prismatic jointing of the basalt, and 18 is a good example of the same rock exfoliating into spheres, a very characteristic mode of weathering. The general appearance of basalt outcrops, weathering into step-like cliflfs with sloping terraces between, is admirably rendered in 34, and the grand coast cliffs of basalt by 75. Glacial phenomena again can be well illustrated. D. 35 shows a section of boulder-clay at Sutton on Howth, and the top of several other sections is formed of the same deposit (73). Large bouiders in Wexford (36), a perched block near Killarney (39), one in Ulster (84), and a Rocking-stone in Island Magee (45) (probably the same as the photograph, 79), give a good idea of the massive materials carried by ice for great distances. The graceful outlines and sweeping curves of groups of eskers are well shown in 37 and 38, while the Devil's Punch- Bowl near KiUamey (4) is an example of a lake dammed by a glacial moraine. Coming to modem phenomena, the power of marine denudation in carving away a coast is shown by the sea stacks, chiefly from the northern coast, in 41, 54, 55, 59, 62, 64, 65, 66, and by one of the photographs (70), which depicts a pump now surrounded by the sea, but originally erected in 1824 or 1825 to pump water from a sandstone quarry, which was then at some distance from the sea. A valley cut through the Tertiary Basalts is shown in 74. The sea stacks in 57 are raised far beyond the reach of the sea, and are connected in date with one of the raised beaches on the Antrim coast. The rest of the drawings and photographs are devoted to illustrating the cliffs or outlines due to different types of rooks, Silurian and more ancient rocks, 70, 74, 82, 85, 86, 87, and 88 ; Old Red Sandstone, 6, 10, 1 4, 1 5, and 79 ; and Carboniferous rocks, 70, 71, 81, 88, 91, and 92. The Maps. The upper part of each wall-case contains one or two maps made up from the sheets of the 1-inch Geological Survey map, to represent some striking or important area of igneous rocks, which is illustrated by the collection of rocks placed below. The follow- ing is a list of the maps : — A. The northern and southern part of the great Leinster Granite and its bordering rocks. B. The area of Carlingford and Clogher Head. Dublin, Lambay and Portraine. C. Mid-Mayo, Achill Island, Clew Bay, and the Oi Mountains. D. South Mayo and Galway (the continuation of C to' the South). 130 THE ILLUSTIUTIONS. E. The northern part of the area of Granitic and Foliated Rocks in Donegal. ' F. Coloured table of the succession of Strata in Antrim. The Volcanic Plateau of Antrim. G. The Igneous feocks of the Waterford Coast. . " The Igneous Tract of KUlarney and Lough Guitane. The Limerick Carboniferous Volcanic Tract. The Sections and Plans. The Horizontal Sections represent what would be seen if a deep canal were cut right through the country in such a direction as to show best the structure and mutual relations of its com- ponent rocks. The Vertical Sections show what would bq. seen if a deep shaft were sunk through the rocks at right angles to their surface. The districts chosen are remarkable for the peculiar structure and relations of the rocks or for their economic value. The following is a list of them : — Sorizontal Sections. 1, Sheet 24. — (a.) From the entrance of Carlingford Lough to Newcastle, across Silurian rocks, , the Mourne Granite, and its offshoots and dykes. ■ (6.) From KUlinchy across Scrabo Hill to Cultra, showing Silurian, Carboniferous, Permian, and Triassic rocks, and the Ter- tiary Basalt. 2, Sheet 29.— 'From Carrickfergus to Fair Head and Rathlin Island, showing the relation of the Basalts to Foliated, Old Red, Carboniferous, Triassic, and Cretaceous rocks. 26, Sheet 34. — Across Donegal from the Fin Valley by Errigal Mountain to Bloody Foreland. Foliated and Plutonic rocks. 30, Sheet 26.— (a.) From Killary Harbour to Clew Bay; : Foli- ated, Silurian, and Carboniferous rocks. (6.) From Moher Lough to Lough Mask. Silurian rocks. . , 80, Sheet 10. — Across the Slieve Atdagh Coalfield, Tipperary. 51, Sheet 14. — Across Hqwth and parts of Dublin, showing Cambrian, Silurian, Carboniferotis, and Intrusive rocks. . , ■ Vertical Sections. 42. — 25 Shafts in the Castlecomer Coalfield. Plans. 11. — The Ovoca Mines, Co. Wicklow. Small Drawings, &;c; At the sides of the wall-cases will, be found a series of sin;i]l di'awings, chiefly from illustrations published in the, Survey Memoirs, some by Sir A. Geikie and the ' rest by Mr. M^Henry, intended to illustrate still further numerous points connected with the structure, scenery, and economic utility of the rocks displayed in the cases themselves. An attempt has been made in one of thorn to show in a diagrammatic fashion the age, character, com- position, and relations of the igneous rocks of Muuster. 131 INDEX INDEX TO PLACES FROM WHICH THE ROCK SPECIMENS DESCRIBED IN THIS GUIDE HAVE BEEN COLLECTED. Eeg, No. Locality. One-incli Map. t260 Mount Charles Quarry, Donegal, 23 x386 Kilwarlin Cottage, Moira, Down, 36 396 Scrabo Hill, Down, 'i . ' 37 516 li miles W.S.W. of Pettigo, Donegal, . 32 517 2 milesW. of „ „ ' . . 32 ■518 • )> JJ )J )> ■ • 32 520 3 „ W.N. W. of „ „ . . 32 522 4 32 523 )j jj >j jj )) • ■ 32 524 J) )> J) 3J )) ' * 32 527 1 mile N.W. of Black Gap, near Pettigo, Donegal, ...... 32 531 1 mile N.W. of Black Gap, N.W. of Pettigo, Donegal, . • . 32 534 Lough Nadarragh, Donegal, 32 560 3| miles S.E. of L'aghy-, Donegal, 32 561 7 miles N.E. of Pettigo, Tyrone, . 32 566 4 miles N.E. of Laghy, Donegal, . 32 572 Essan Burn, 4 miles S.W. Killetter, Tyrone, 24 584 Bunbeg, Donegal, .... 9 591 Meenabraddan Mt., Donegdl, 10 592 Fintown, Donegal, . . 16 605 Torr Head, Antrim, •. . ' . . . 8 607 1) >!' 3» :- ■' ■ , • 8 608 >J 3) 33 . . . ' . 8 609 Near Cushendall, Antrim, . . . • 14 610 5) 33 33 " • ■ • 14 613 33 ^ 33 33 e . 1 • 14 614 Colliery Bay, Bally castle, Antrim , • , , • 8 618 N. of Hollywood, Down, . . . • 29 619 Murlough Bay, Antrim, • 8 623 Clonfeadi, Crew, Tyrone, .... 46 x2 132 Index — continued. Beg. No. Locality. One-inch Map. 624 Portrush, Antrim, 7 626 Ballintoy, Antrim, 7 627 Glenarm, Antrim, . . . . . 20 628 Murlough Bay, Antrim, . . . . 8 632 N.N.E. of Ballycastle, Antrim, . 8 633 6 miles E. of Ballycastle, Antrim, 8 635 Portrush, Antrim; 7 636 Fair Head, Antrim, 8 637 Ballygally Head, Antrim, . . . . 21 638 White Mountain, Derry, .... 18 639 Boughillbriga, Derry, 18 640 I mile W. of Ballycastle, Antrim, 8 641 >i )i » • • 8 642 I) » 1! • ■ 8 643 >! J) )) • • 8 646 Mweelrea Mountain, Mayo, 84 647 Lough Fee, Galway, 84 648 W. of Tullyconner Bridge, Galway, 94 649 )> J' » jj • ■ 94 651 Lacken, near Slieve Baun, E,oscomnu>n, 88 653 Ballymore, Roscommon, .... 87,88 655 Gregg Quarries, Galway, 93 656 » » !) .... 93 657 Derrybeg, W. side, Galway, 94 658 Lurgan, Loughanillaun, Galway, 94 661 Ventry, Kerry, 171 662 Brandon Mt., Kerry, 165 663 Glenflesk, KeiTy, . ... 185 665 Ventry Harbour, E. side, Kerry, 171 666 Bear Island, Cork, 198 667 Tunnel between Cork and Kerry, 192 672 Kiln Point, Lambay Island, Dublin, 102 674 Kilmagar, Kilkenny, .... 147 675 Near Bagenalstown, Carlow, 147 676 Moynaivy, Meath, 101 677 Daranmona, Galway, ..... _ 678 Near Rinekirk Point, Limerick, . 143 682 Sheet 14/1 six in., Longford, 88 684 Kiln Point, Lambay Island, Dublin,. . 102 685 )i , » )> - • 102 • 687 Killaquile, Knocksefin, Galway, . 105 689 Near Tamney, Donegal, .... 4 691 Church Hill, Knockateen Beg, DcmegaJ, 16 692 J1 JJ 3, JJ 16 695 Clare Island, Mayo, ..... 73 133 Index — continued. Reg. No. Locality. One-inch Map. 696 Sheet 98/3 six in., Mayo 84 698 Donaglienry, Tyrone, . 35 699 ■1- mile W. of Castlebar, Mayo, 75 700 2 miles N.W. of „ 75 701 7 miles W. of Westport, „ 74 702 ShannauDafeola, Galway, 94 705 Moyne, Mayo, .... 53 706 j> ?»•••• 53 707 Lough Allen, Roscommon, . 66 711 Newtown House, River Slaney, near Wexford, .... 158 712 Devil's Glen, Wicklow, 130 713 I) » )) • ■ • 130 715 Ballyvarney, Wexford, 168 716 Balbriggan Slate Quarry, Dublin, 92 717 Rathdrum, Wicklow, . 130 718 Balbriggan Slate Quarry, Dublin, 92 721 Kerloge, Wexford, 169 722 U )>'••* 169 723 Slieve Baun, Roscommon, . 88 724 1 mile N. of Coolrain, Queen's County, 127 725 Catstown, Kilkenny, . 157 726 Crumlin Quarries, Dublin, . 112 727 Red Cow, Dublin, 112 728 Howth, Dublin, .... 112 729 Kilbline, Kilkenny, 147 730 Milltown, Dublin, 112 731 4 miles N. of Edenderry, Kildare, 110 732 jj ») J) ') 110 733 Hook, Wexford, .... 179 735 Balbriggan, Dublin, 92 736 Termonmaquirk, Athenree, Tyrone, 34 737 Kildare, _ 733 Near Ballinagappoge Bridge, Wicklow, 129 739 )j »j jj »j • • 129 743 Near Camp, Derrymore Glen, Dingle, Kerry, 161 744 J) )I )> !> )) )) 161 746 Near Anascaid, Kerry, .... 172 748 Dinglej Kerry, .... 171 749 J) J) • • • 171 750 Brandon Mt., Kerry, . 161 751 Ventry Harbour, Kerry, 171 754 W. of Doulns Head, Kerry, 182 756 E. side of Smerwick Harbour, Kerry, 160 759 Railway Station, Waterford, 168 134 Index — continued. Reg. No. Locality. One-ineh Map. 760 Tncliigeelagl), Cork, . . . . 193 773 Ballynahinch, Limerick, 154 775 Mallow, Cork, , . . . 175 777 Carrickeengullia, Kerry, 173 778 Mallow, Cork, .175 781 N. Glengoole Colliery, Tipperary, 146 782 Parknatilla, Kerry, ..... 142 783 Ardmore Point, Keriy .... 141 784 J) jj ^ jj ^ 141 785 MeenyHne S., Limerick, . . 152 786 2 miles W. of Ardagh, Tjimerick, . 154 787 )) jj )j J) * • 154 789 Knockinglass Colliery, Tipperary, 146 790 Salthill, near Kingstown, Dublin, 112 792 Mitchelstown, Cork, . . '"'."'. 165 793 Minane, Cork, ...... 195 794 N. of Loghill, Limerick, .... 142 795 Knockinglass Colliery, Tipperary, 146 796 Ferriter's Cove,' Kerry, 171 799 Fermoy, Kilwoi-th, Cork, 176 801 Desertcreat, Tyrone, . . ■ . ,34 803 Ardtrea, Tyrone, . . , • ,. 35 805 Between Belfast and Lisburn, Antriiii, 36 806 Monaghan, ..... __ 807 Killyman, Tyrone, ..... 35 809 Larne, Antrim, ...... 21 810 1 mile N.E. of Lame, Antrim, 21 811 Lame, Antrim, . . . . . , . 21 812 S. of Bryantang, Antrim, .... 29 813 Colin Glen, 5 miles S.W. cf Belfast, Antrim, 36 814 , Colin Glen, Antrim, . . . . . 36 819 Derryveagh, Donegal, . 10 820 Glenshesk, Antrim, . 8 822 Cusbendun, Antrim, . 14 823 Inisbbofin Island, Donegal, 3 830 Tyrone, _ 831 Portrush, Antrim, 7 832 Near Glenarm, Antrim, . ,20 835 WJiite House, Island Magee, Antrim, . 21 836 Waterloo House, near Lame, Antrim, 21 837 )j )) ») 3> ; 55 • 21 839 Whitepark Bay, Antrim, .... 7 841 Near Waterloo House, Larne, Antrim, 21 842 N.W. of Baily Lightliotise, Howth, Dublin, . 112 845 E. of Harbour, Howth, Dublin, . 112 13§ Ind ex — continued. Reg. No. Locality. One-inoh Map. 846 E. of Harbour, Howth, Dublin, . . '. 113 847 )) , )) 1) J) • ■ ■ 112 848 Gibbet Hill, Waterford, . 168 849 jj jj )j • • ■ • 168 851 Gafiyduff, Kilkenny, . . . . 147 852 Duncormick, Wexford, 169 853 Cranroe, Kilkenny, . ." 147 854 1 miles S. of Castlecoine]?,' Kilkenny, . 137 S55 Sheet 6/1 six in., Carlow, 187 856 Skreen, Sligo, . .... 54 857 ,,,,.... 54 859 5 miles S.W. of Louisburg, Mayo, 84 860 )j J) )) )» • • • 84 861 Croaghan, Mayo, . . ' . 53 864 1-^ miles S. of Wexford, .... 169 865 Bear Island. Cork, . ,'.''. 198 867 Rineen House, Clare, . ■. ' . 123 868 Fair Head, Antrim, ..... 8 869 L. Nafooey, Galway, . ... 94 872 N. of Glen Bridge, Colin Glen, Antrim, 36 874 3 miles N. of Castlebar, Mayo, 'lb 875 : S.W. Leenaun, Galway, .... 84 877 Kennycourt, Kildare, ..... 120 878 Comer of Sheet 20/4 six in., Wexford, 158 880 Near Lou"h Macournane, Glastrasna, Kerry, Near Dunboy Demesne, Desert, Cork, 192 882 198 883 Near Inch, Dingle, Kerry, .... 172 887 Tiernakill, S. Galway, .' 94 895 Mitchelstown, Cork, .... 165 901 N.E. of Newtown Stewart, Tyrone, 25 902 Cookstown, Tyrone, ..... 27 904 Near end of Boa Island, Fermanagh, . 32 905 1 mile W. of Bundoran, Donegal, 31 907 Between Fair Head and Ballycastle, Antrim, 8 908 Shore between Fair Head and Ballycastle, Antrim, 8 910 3 miles N.W. of Carrickfergus, Antrim, 29 912 Bray Head, Wicklow, 121 914 Bellewstown,' Meath, . . . . 91 915 Hook Head, Wexford, 169 916 Quillia, Waterford, ..... 179 920 N. of MuUaghinarky, Kerry,' 162 923 Salrock, S. of Killary Bay Liteie, Galway, 84 924 )) )) ' ?j )) >j )j 84 928 5 miles S. of Louisbiirg, Mayo, 84 136 Indkx — continued. Eeg. No. Locality. One-inch Map. 929 S. of Cregganbaun, Mayo, 84 930 2i miles N."W. of Arigna Iron Works, Roscommon, . . . . . 66 932 Creevalea Iron Mine, near Drumkeeran, Leitiim, . . .' 56 935 Lough Derravaragh, West Meath, 89 936 Carlan, Fana^, Donegal, : . . . , . 5 941 Manorcunningham, Donegal, . . ;i . 17 943 S.E. of Castlederg, Tyrone, . . . - . 25 946 Corkhill, Pomeroy, Tyrone, 34 944 Near, Donaghmore, Tyrone, 34 945 Killymaddy Bay ? [Lough ?], Tyrone, 34 947 St. Johnstown, Donegal, . . 17 949 >j , jj .... 17 953 1 mile N. of Lougb Greenan, Donegal, 10 956 Barnesbeg, Donegal, . . ... 10 957 j> i> ..... 10 958 )) JJ • . .;.',. 10 962 Dunfanaghy, Donegal, 4 963 Fanad within Water, Donegal . 4 965 Kindrum, Fanad, Donegal, 4 967 N. side Muckish Mt., Donegal, . 10 970 Inishdboey Island, Donegal, 3 971 Tieveragh Hill, N. W. of Cushendall, Antrim, 14 972 Scawt Hill, 4 miles S.S.E. of Glenarm, An- ti'inOj . . . 20 976 Scawt Hill, 4 miles S.S E. of Glenarm, An- trim, ...... 20 977 Templepatriok Quarry, Antrim, . 28 979 Scawt Hill, Antrim, 20 980 Libbert Mine, | mile S. of Glenarm, An- trim, ....... 20 981 " " ji 20 983 " I' I) 20 984 " >> II 20 985 " " II 20 987 . " " n 20 988 2 miles S.S.W. of Ballintoy; Antrim, 7 990 " •> 1, . . 7 993 Parkmore, Antrim 14 995 6 miles N.E. of Ballymena, Antrim, 20i 998 2 miles S.S.W. of Glenarm, Antrim, 20' 999 6 miles N.E. of Ballymena, Antrim, .' \ 20 1003 S. of Killary Harbour, Galway, . 84 1006 Glenilesk, Kerry, 185 137 Index — continued. Keg. No. Locality. One-inch Map. 1007 1008 1010 1011 1012 1013 1014 1016 1017 1019 1020 1022 1023 1024 1025 1026 1028 1032 1035 1036 1037 1039 1041 1042 1043 1047 1048 1049 1050 1053 1054 1059 1061 1062 1067 1069 1070 1071 1074 1075 1077 1081 1084 1085 5 miles N'.W. of Kenmare, Kerry, S.E. of Suspension Bridge, Kenmare, Kerry, Mulgrave Barracks, Killarney, Kerry, N. of Looscaunagh Lough, Kerry, Coosaun Lough, Diinloe, Kerry, Near Black Lake, „ „ Moroe, Limerick, 6 miles N. of Limerick, Clare, Cratloe Hills, Clare, . Near Monkstown Church, Cork, . 1 mile N.W. Coomhola Bridge, Cork, R. C. Chapel, „ ,, „ 3 miles N. of Bantry, Cork, )j » J) )) ' Glasheen, 1^ miles S. of Cork, Flaxfoot, Little Island, Cork, Little Island, Cork Harbour, 3 miles N. of Mitchelstown, Slieve Galty Tipperary, .... 8.W. of Tramore, Waterford, Tunnel between Cork and Kerry, Cultra, Down, .... Island Magee, Antrim, Cliffs near Giants' Causeway, Antrim )) J' )j J) J) Murlough Bay, Antrim, Bloody Foreland, Donegal, . Keeldrum, Donegal, . InishtrahuU Island, Donegal, Tamney, Donegal, N. of Tamney, Donegal, [Lackagh Bridge?], Donegal, Lackagh, Donegal, Dunfanaghy, Donegal, Oughtdorragh, Donegal, Lackagh, Donegal, Drumboghill, Donegal, Little N.E. of Lodge, Donegal, Little N.E. ■ " ", ~ Crohy Head, Donegal, Thonevancil, Donegal, W. of Ballybofey, Donegal, Lough Alaan, Stranorlar, Donegal, N.E, of Moville, Donegal, . of the Lodge, Donegal, 184 184 184 184 173 173 144 143 143 195 195 192 192 192 192 187 187 187 165 179 192 29 21 7 7 8 9 9 7 4 4 10 10 4 10 15 15 16 16 15 16 24 24 6 138 Index — continued. Beg. No. Locality. One-inoh Map. 1086 4 miles N. of Moville, Donegal, . 6 ld87 1^ miles N.N.W. of Moville, Donegal, H 1088 Moville, Donegal, . "." ;. 6 1092 Slate Quarry, St. Johnstori, Donegal,; . 17 1093 J) )V ■ , jj )) • •■ 17 10&4 Balbane Hill, Donegal, ' . . '. 23 1103 Garvary, N. of Castlecaldwell, Fermanagh, . 34 1105 Black G-ap, near Pettigo, Donegal, . . 34 J 108 Garvary, N. of Castlecaldwell, Fermanagh, . S2 1109 N.W. of Pettigo,^ Donegal, . '32 1112 Moneyneany, Derry, . . 18 llU Oughtagh, Donegal, ■ . 22^23 1^7 4 miles N. of Pomeroy, Tyrone, '. , . 26 1119 S. of Loilisbnrg, Mayo, . S4 1120 N. of GlencuUia Lake,- Doolough, Ma^d, 84 1122 Mutton Island, Galway Bay, 105 1123 Ox Mountains, Sligo, . 54 1126 Erris Head, Mayo, ..... 39 1128 j» tj ■ . , * 39 1129 )J 3J • • • • 39 1130 ,, ,, -..'., 39 il31 Erris Head ? Mayo, . . . 39 1132 Eagle Island, Mayo, . . ... 39 1134 Iniskea Island, Mayo, . . , , . 51 1135 51 4138 Annagh Head, Mayo, . .' 51 1145 Doolough Pt., Mayo, . . . 51 1146 Gubarusheen, Mayo, ' . . . . . 51 1148 Achill Island, Mayo, . . . . 62 1149 )>))»!• ' : • 62 1150 Achill Sound, Mayo, 1 ■ . . '; ' '63 1151 Curraun Achill, Mayo, .... 74 1153 3 miles S.W. of Westport, Mayo, . ' . " 74 1154 Deerpark, ' „ " ■ .74 1155 1157 Croaghpatrick, „ „ '. . ' 74 Sheet 10/1 six in., Galway, . • . 83 1159 Grallagh, Galway, . . ' 93 1158 Maumeen Bay, S. of Olifden, Galway, . 93 1161 Mullaghglass Shore? Galway, 83 1162 Olifden, Galway,;' ■. . 93 1164 Streamstown, Olifden, Galway, . 93 1165 ,) »»•••• 93 1166 „ J) ji • • • . 93 1167 ,. J, " , * 93 1169 Gregg Quarries, Galway, . 93 139 Iis'DRX — continued. Reg. No. Locality. Oiie-iHch Map., 1170 Crogg Quarries, Galway, 93 1173 Ballycoixaeely, Galway, 95 1175 N. of BaUyconneely Bay, Galway, 93 1178 Learn East, Galway, . ... 94 1181 Recess, Galway, . . . 94 1182 [Recess 1], Galway, . .''' . 94 1183 [Recess'!], „ . 94 1184 Illaunakniok, Galway, .... 95 1185 Dooms, ,, . . . 95 1187 Cannaver Island Galway, .... 95 1189 Cannaver Island South, Galway, 95 1190 )j ji jj n ■ ■ ^ ■ 95 1191 Cannaver Island South, Lough Corrib, Galway, . . . . 95 1192 Cannaver Island, Lough Corrib, Galway, 95 1193 )) J3 J) . • ■ 95 1195 )J )? >) ' 95 1197 [One of Islands on Lough Corrib], Galway, 95 1200 Slyne Head, Galway, 105 1213 Killiney, Dublin, 112 12]5 Near Redcross, Wicklow, . . . 130 1216 Between Luggalaw and Sallygap, Wicklow, . 121 1218 Camaross Mt.j Wexford, .... 158 1220 -J- mile N. of Baily Lighthouse, Howth, Dublin, 112 1222 N. of lower end of Devil's Glen, Wicklow, . - 130 1223 Devil's Glen, Wicklow, . . ' 130 1224 1' ,, ?»••••• ' 130 1226 Derrylossary, Wicklow, 130 1227 Ballinahinch Upper, Wicklow, 121 1230 Haynestown, Kildave, 120 1231 ,, ...... 120 1234 Kilcommon, Wicklow, .... ' 130 1238 Ballin [gate] Carnew, Wicklow, . ' . 148 1243 2 miles N. W. of Freshford, Kilkenny, 136 1244 Dublin, ... . . - 1248 Killiney Strand, Dublin, .... 112 1250 Killiney, Dublin, 112 1252 Glenmacnass, Wicklow, .... 130 1257 S. ofLugnagun Great, Wicklow, 120 1259 Glenbrien, Wicklow, . . ... 129 1260 Graigue-na-managh, Carlow, 157 1262 Above Drumgoff Hotel, Glenmalurs Wick- low 130 1265 St. MuUin's, Wexford, 157 140 Index — continued. Eeg. No. Locality. One-inch Map. 1266 Polmounty, near New Ross, Wexford, 157 1270 Ballinaclash, Wicklow, . . . . 130 1271 S. of Rathdrurn, "Wicklow, 130 1275 W. side of Caherconree, Kerry, . 161 1276 Between Dingle and Anascaul, Kerry, 161 1277 Inch, Dingle, Keny, . 172 1278 Horse Island, Cork, . 199 1279 Near Clonnftl, Tipperary, . 166 1280 Boulea Pit, near Killenaule Tipperary 146 1282 ^ miles N.W. of Slane, Meath, . 91 1283 3 miles N.W. 91 1286 3A miles N. 91 1291 3| miles N.W. „ „ 91 1294 2 miles N. „ „ 91 1296 \ mile N. ,, „ 91 1298 1 mile N. E. 91 1299 ^ mile N.E. „ „ 91 1302 f mile E. „ „ 91 1303 Baronstown Cross, near Slane, Meath, 91 1305 Craig's Cross, near Navan, Meath, 91 1311 2 miles N.E. of Kingscourt, Cavan, 81 1314 Kingscourt, Meath, 81 1315 Barleyhill, Meath, 91 1317 Ardagh Church, Meath, 81 1819 IJ )» 5> 81 1322 2 miles N.W. of Kingscourt, Cavan, 80 1323 4^ miles W. „ „ 80 1326 4 miles W. of „ ,. 80 1328 Kingscourt, Meath, 81 1330 2 miles S. of Kingscourt, Meath, 81 1332 Kingscourt, Meath, 81 1333 2 miles S.E. of Kingscourt, Meath, 81 1336 ■> )) J) !1 81 1337 1 miles N.E. of Armagh, . 47 1339 ^ miles S. of Armagh, 47 1343 J mile „ 47 1347 1 mile „ ... 47 1348 Marble Quarry, Armagh, . 47 1353 Bichhill, Armagh, 47 1355 ^ mile E. of Armagh, 47 1357 i mile N.W. of Grange, Tyrone, '35 1360 : mileS.W, „ . . . 35 1362 '. "ullyconnell, E. of Grange, Tyrone, 35 1366 ■ : mile S. W. of Ardtrea, Tyrone, 35 1369 mile S. of Cookstown, Tyrone, . 27 141 Index — continued. Eeg. No. Locality. One-inch Hap. 1372 1373 1376 1384 1389 1400 1408 1410 1411 1415 1416 1419 1423 1425 1428 1433 1434 1436 1438 1440 1441 1443 1446 1449 1453 1456 1457 1458 1460 1464 1465 1468 1470 1474 1478 1481 1484 1486 1487 1488 1490 1492 1495 1496 S. end of Cookstown, Tyrone, ^ mile S. of Cookstown, Tyrone, Near Dungiven, Derry, Eiver Eae, ^ mile S. of Dungiven, Derry, \ mile S. of Dungiven, Derry, 1 mile W. of Park, Derry, \ mile W. of Lisbellaw, Fermanagh, . 1 mile W.N.W. of Lisbellaw, Fermanagh, )' J) ?) ^ mile E. of Lisbellaw, Fermanagh, J mileW. ,, „ S.W. of Lisnaskea, Fennanagh, . 2 miles E. of Lisnaskea, Fermanagh, . Lisnaskea, Fermanagh, Carrascoffy Bridge, Leitrim, 4 miles S.W. of Mohill, Leitrim, j» J) Mucklougher, Leitrim, ... J mile E. of Workhouse, Granard, Longford 11 mile E. of Granard, Longford, N. of Granard, Longford, Lough Eask, Donegal, >j )) j> • • S.E. corner of L. Eask, Donegal, ^ mile E. of Lougli Eask, Donegal, 1 mile E. ,, ,, 1 mile S.W. of Barnes Lough, Donegal Bamesmore, Donegal, W. of Lough Craig, Donegal, Keadew Bridge, Donegal, ^ mile W. of Donegal, 4 miles N.E. „ 2 miles iN'.E. of Donegal, i mile W. 2 miles E. of Ballyshiinnon, Donegal, . 2 mUes E. of Ballyshannon, Donegal, . 1 mile N.W. of Belleek, Donegal, Farrancassidy Cross Eoads, Fermanagh ■1 mile W. of Carricknagower Lough, Fer managh, ...... 27 27 18 18 18 18 45 45 45 45 45 57 57 57 57 78 78 78 78 78 78 79 79 79 24 24 24 24 24 24 24 24 85 24 24 24 24 24 24 31 31 32 44 44 142 Index — continued. Beg; No. Locality. Onc-ineli Map. 1498 1 mile S. of Glenalong, Fermanagt, 44 1499 3) >J )? • - '■44 1504 Carricfcnagower Lough, Fermanagh, 44 1505 S. of Carricknagower Lough, Fermanagh, . 44 1507 \ mile N.E. of Glenbridge, Fermanagh; 44 1512 Near Carricknagower Lough, Fermanagh, . 44 1516 Mountfield, Tyrone, 26 1517 IJ )1 • r . . 26 1520 W. of,, „ . . . . 26 1523 • 33 JJ 33 • • 26 1527 S.E. „ „ „ . . . 26 1531 Omagh, Tyrone, '. . . . 33 1539 1 mile W. of Corlea 'School, Tyrone, 33 1541 If miles W. ,, „ . . 33 1542 ^ mile S. of Longfield Glebe, Tyrone, . 33 1545 Aghadulla, Tyrone, ' . .' - 33 1547 ' 33 33 ..... 33 1550 Dromore Crossing, S. of Omagh, Tyrone, 33 1552 , 2 miles N. of Crossdoney, Oavan, 68 1553 Lisnamandra, Cavan, ..... 68 1555 1 mile N. of Crossdoney, Cavan, . 68 1556 33 33 53 * • ' 68 ,1557 1 mile S. „ „ . . 79 1559 1 mile N. „ „ . . . 68 1561 Bellahillan Bridge, N.W. of Crossdoney, Cavau, 68 1563 1 mile 'S.'W. of Bellahillan Bridge, Cavan, . 68 1565 E.S.E. of Casey's Lough, Cavan, . 79 .1568 1 mile S. of Crossdoney, Cavan, . , 79 1571 1 mile S. „ „ . 79 1573 1| miles S. of Crew Church, Tyrone, . 25 1576 Magheralough, Tyrone, • '■■ . 25 1582 N. of Lisnacloon Bridge, Tyrone, 25 1587 Lisnacloon Bridge,' Tyrone, .... 25 1593 fmile S.W. of Capard House, Queen's Co., . 118 ^1595 33 33 33 , 33 , 118 1597 1 mile S.S.W. of Rosenallis, Queen's Co., 11-8 1898 B.C. Chapel, • ;, 118 1600 Mountmellick, Queen's Co., 118 1602 1 mile S.E. of Clongowan, King's Co., 118 1604 S.W. side of Croaghan HUl, at G6rteen,King's Co., . , . . . 109 1606 S.W. side of Croaghan HUl, atGorteen, King's J Co., 109 1G08 Croaghan Hill, King's Co., . 109 143 Index — continued. Rog. No. Locality. Oneyinch Map. 1610 \ rnileN. of Cairn, Croaglian Hill, King's Co., 109 1613 W. of Cairn, Croaghan Hill, King's Co., ; 109 1614 imileN.E. of Cairn, Croaghan Hill, King's -Co., ....... 109 1619 2 miles E. of Phillipstown, King's Co., 109 1621 )) j> )) >j 109 1622 \ mile W. of Loughrea, Gal way, . 115 1627 51 miles N.W. 115 1628 >j )) j> jj 1.15 1631 1 mUe E. of Castleboy, Galway, 115 1632 li miles E. 115 1635 M )) )) ' 115 1636 J) >» J? 115 1638 jj )» )j 115 1640 ■ » r) )j -' -■>••" •■■- 115 1644 3^ miles S. of Gort, Galway, 124 1646 5 miles S. „ „ 124 1654 1 mile S.E. of Scalpiiagown, Clare 124 1660 8 miles S. of Gort, Clare, . 12,4 1662 )) )5 Ji 12,4 1663 \ mile N.E. of Cloonagro, Clare, » 124 1665 3 miles N.E. of Crusheen, Clare, , 124 1666 2i miles N.W. of Killala, Clare, . 134 1668 If miles "W. of Silvermines, Tipperary, 134 1670 If miles W. of „ „ . . 134 1672 \ mile S.W. of „ „ . . 134 1675 1 mile S.W. of „ „ . . 134 1676 N. of BaUina, Tipperary, .... 134 1678 1 mile W. of Silvermines, Tipperary, . 134 1679 N. of Ballina, Tipperary, .... 134 1680 BaUina, Tipperary, . . . . . 134 1682 „ ,, . . . . . 134 IB'85 1-| mUes E. of Balliiia, Tippeiury,' ■ "' 134 1689 1 mile S. of Mt. Bruis, Tipperary, 154 1691 1\ miles S.S.E. of Mt. Bruis, Tipperary, 154 1693 1^ miles S.E. Mt. Bruisi Tipperary, . 154 1695 1) )J 5) . » , * • 154 1699 1 mile S. of Stagdale, Tipperary, 154 1701 J) 5J • • 154 1702 )) '» r,, • 154 1705 Knookmpyle Mountain, Tipperary, . , . m 1707 Base of Knockmoyle Mt., 'Tipperary, . ,154 1713 4 miles E.N.E. of Kanturk, Cork, 175 1715 If 3J J) • ■ 175 1722 3 miles E. „ , , . . 175 14,4 Index — continued. Eeg. No. Locality. One-inch Map. 1724 4 miles E. of Kanturk, Cork, 175 1726 ?» )),;!••* 175 1729 2i, miles S.E. „ „ . . . 175 1730 2 miles S.W. „ „ . . . 175 1734 2 miles E. „ „ . . 175 1736 1^ miles E. „ „ • . 175 1744 Mallow, Cork, 175 1745 1 mile E. of Scalpnagown, Clare, 124 1746 2 mile W. 124 1747 - mile N. of Cloonagro, „ 124 1749 mile N.E. of Scalpnagown, „ . 124 1750 [Annalong] Kilkeel, Down, 61 1752 Glendalough, Wicklow, . . . . 130 1753 Bally raine Lower, Wicklow, 139 1754 Glenart Castle, Arklow, Wicklow, 139 1756 Knockatober, Wexford, .... 148 1757 New Ross, Wexford, .... 168 1758 4J mUes S. of Thpmastown, Kilkenny, 157 1759 N. boundaiy of Bryanstown, Meath, . 91 ,1760 Craigbaron Hill, Slane, Meath, ; 91 1761 S. of Grangegeeth, Meath, . ' . . 91 1762 Lough Barra, Doochary, Donegal, 16 1763 Athenree,' Tyrone, 34 1764 Gortacloghan, Tyrone, 19 1765 S.E. of Eostrevor, Down, .... 71 1806 Crossfernoge Point, Wexford, 180 1874 Tramore, Waterford, .... 179 1882 Caher, L. Graney, Clare, .... 124 1883 W. Shore, Killala Bay, Mayo, . 53 1884 f Ballaghaderin area ?] Mayo, 76 1886 Waterloo Bridge, Clifden, Galway, 93 1888 Townpark, Galway, . ... 105 1889 Ballard, Galway, . . 105 1891 Bunnagippaun, Galway, . . 1891 1894 Lambay Island, Dublin, .... 102 1896 Rue Bane Point, Fair Head, Antrim, . 8 1898 Crohy Head, Donegal, .... 15 1900 Near Castlefinn, Donegal, . 25 1903 Shore at Ballywalter, Down, ... 37 1904 Slieve Gullion, Armagh, .... 59 1905 Moume Mountains, Down, ... 48,49 1906 3 miles N. W. of Downpatrick, Down, 49 1917 Granite, Ballyknockan, Wicklow, 120 1926 Granite, Glenmalure, Wicklow, . 130 1927 Granitite, Glenmalure, Wicklow, 130 145 Index — continued. Reg. No. Locality. One-inch Map. 1928 Granite, Glenmalure, Wicklow, 130 1931 Granite, Graignaspiddoge, Carlow, 137 1935 Gap of Sculloge, Wexford, 148 1937 Near Ballinaclash, Wicklow, 130 1942 Clonroe Bridge, Wioklow, . 139 1944 Ballymottymore, Wexford, 158 1945 Granite with tourmaline, Ballyedmonduff, Dublin, 121 1946 Dalkey, Dublin, .. ... 121 1947 „ )j • • ' • • 121 1948 Ballyedmonduff, Dublin, 121 1950 Derrylossary, Wicklow, 130 1951 Mullinacuff, near Tinnaliely, Wicklow, 138 1952 Barnacullifl., Dublin, . 112 1953 Dalkey, Dublin, ... 112 1956 Near Dundrum, Dublin, 112 1957 Polmounty, Wexford, 157 1958 Near Blessington, Wicklow, 120 1960 Rathdrum, Wicklow, 130 1961 Near Rathooole, Dublin, 111 1964 Raheenavine House, Wicklow, 139 1968 2 miles S. of Arklow, Wicklow, 139 1979 Crogban "Kinshela, Wexford, 139 1981 Bree Hill, Enniscorthy, Wexford, 158 1985 Balleese, Wioklow, 130 1987 Tullylusk, S.E of Rathdnnn, 130 1991 Kilbride, Wicklow, . , . 139 1994 S.E. of Gorey, Wexford, . 149 1996 Cherryorchard, near Enniscorthy, 158 2002 W. of Brittas Bridge, Wicklow, 130 20'J9 Dunlavin, Wicklow, ..... 120 2010 Balleese Wood, Rathdrum, Wicklow, 130 2012 Corballis, near Rathdrum, Wicklow, . 130 2017 Arklow Rock, Wicklow, 139 2018 Arklow Head, Wicklow, .... 139 2023 S.W. of Enniscorthy, Wexford, 158 2024 Bree Hill, Wexford, . 158 2026 Baltyboys, Wicklow, 120 2028 Ti-Clash, Rathdrum, Wicklow, . 130 2030 Granitite, Glenmalure, Wicklow, 130 2032 S.W, of Gap, Croghan Kinshela, Wexford, 139 2040 Rochestown, Kilkenny, 168 2043 Dunganstown, Wicklow, .... 130 2045 Garrigmore, Wioklow 130 2046 )j i^ ' ■ • 130 146 Injdex — continued. ■Eeg. No. Locality. One-inoli Map. 2047 Cumner Place, Shillelagh, Wexford, . 138 2048 Bologe Lower, Wicklow, .... 130 2049 Rock Big, Arklow Eock, Wioklow, 139 2056 Ballythomas, near Croghan Kinshela, Wex- ford, 139 2060 S. of Eoundwood, Wicklow, 130 2063 BscUymoyle, Wicklow, .... 139 2064 Mr. Parnell's Quarries, Arklow Rock, Wick- low, ....... 139 2068 Gflasnarge, Kilcommon, Wicklow, 130 2069 Mount Lusk, Kilcommon, „ 130 2072 Balleese Wood, Rathdrum, „ 130 2074 Ballyologh, Dunganstown, „ 1.30 2075 \ mile E. of Coatstown, „ . . 139 2079 Near Camsore, Wexford, .... 181 2080 jj jj • • ■ . 181 2081 Croaghan Hill, Phillipstown, iKjing's County, 109 2084 Grange Common Hill, Kildare, . 119 2085 Hill of Allen, „ . . . 119 2086 N. of Baily Light House, Howth, Dublin, . 112 2087 Portraine? Dublin, ..... 102 2089 Shore at Portraine, Dublin, 102 2090 Lambay Island, Dublin, 102 2094 5J J) JJ .... 102 2095 JJ JJ >) .... 102 2099 Ardcath, Meath, 91 2100 Bellewstown Hill, Meath, .... 92 2101 Near Racecourse, Bellewstown, Meath, 92 2104 Bellewstown Hill, Meatli, .... 92 2107 Cooksgrove, Meath, .... 91 2108 Duleek, Meath, 91 2109 Gillanstown, Meath, ... 91 2110 Craigbaron Hill, Slane, Meath, . 91 2111 Knockerk, Meath, ... 91 2113 Grangegeeth, Meath, ..... 91 2115 Broom field, Meath, 91 2il9 Oriel Demesne 1 Louth, .... 81 2122 Foughill ? 1 Louth, .... 70 2124 Barnaveve, Carlingford, Louth, . 71 2129 li miles W. of Stradbally, Waterford, 178 2130 Annestown, Tramore, Waterford, 178 2131 ^ mile E. of Annestown, „ . . 179 2132 2 miles N. „ „ . . 179 2140 Great Newtown Head, „ . . 1 179 147 Index — continued. Eog. No. Locality. One-inch Map. 2141 KnockanduflF, Waterford, .... 179 2142 Bimmahon, „ 178 2144 E. of AnnestowM, „ ... 179 2145 Dunhill Castle, „ . . . 179 2151 Mishells, N. of Bandon, Cork, 194 2152 Near Crow Head, Cork, 198 2159 Whiteball Head, „ . . . . 198 2160 Blackball „ „ .... 198 2163 )) >!)'■•■ 198 2164 W. Coast, Bear Island, Cork, 198 2166 jj jj n jj • ' 198 2177 Ardnakinna Pt., Bear Island, Cork, 198 2179 Bear Island, Cork, . ... 198 2181 Clogher Head, Kerry, .... 171 2182 J) j» j> 171 2185 Dunqiiin, Kerry, 171 2191 Benaunmore, Kerry, 184 2193 N. of Benaunmore, Kerry, 184 2194 Benaunmore, Kerry, 184 2195 j) ,j . ... 184 2196 Caher, W. of Lough Graney, Clare, . 124 2200 Caier, Lough Graney, Clare, 124 2201 Maddyboy, Limerick, ... 144 2202 )) )' * 144 2205 Standing Stone Hill, near Oola, Tipperary, 154 2206 » II II 'I " 154 2208 Knockaunavoher, Temptebredoiij „ 154 2214 Knockatancashlane, Limerick, 144 2215 )) II ... 144 2219 1 mile E. of Kilteely, Limerick, 154 2224 1 mile S.S.E. of Cahereonlish, Limerick, 143 2227 1 mile N. of Dromkeen Bridge, Limeriok, . 144 2330 ^ mile W. of Rathfooroge, Limerick, . 154 2233 2^ miles E. of Cahereonlish, Limerick, 144 2234 1 mile „ „ 11 144 2241 Knookseefin, Limerick, .... 144 2242 S. of Nicker, at foot of Pallas Greau Hill, liimerick, 144 2243 Eathjordan, S. of Bally brood, Limerick, 154 2244 11 II 11 ^ " 154 2248 Cahernarrykeane, LiTneiiek, 143 2250 S.W. Quarry, Roxborough, Limerick, . 143 2251 N.E. 143 2254 N. of Meelick House, Carrigogunnell, Lim- erick, 143 148 Index — continued. Reg. No. 2256 2257 2258 2259 2261 2262 2265 2268 2274 2276 2277 2280 2281 2285 2287 2288 2291 2294 2296 2297 2299 2302 2307 2308 2311 2312 3313 2315 2318 2321 2323 2325 2335 2337 2339 2340 2344 2345 2346 234^7 2351 2352 2354 2356 Locality. Wonder Hill, 3 miles 8.E. of Ballybrord, Limerick, . . ' Newcastle,' near Limerick, Clinoe Cottage, near Limerick, JJ Jl )1 3J 2^ miles E. of Limerick, N.E. „ „ ... Ballysheedy House, 2 miles S. of Limerick Carrig Martin, near Cahernarry, Limerick, Dromsallagh, Limerick, Dromsallagh, near Cappamore, Limerick, Near Doon, Limerick, Knockfeerina, near Groom, Limerick, Kilmoylan, Limerick, Knockavilla, Tipperary, Carrigcleena Hill, Cork, Craigrack, Carrigart, Donegal, DunafF Head, Inishowen, Donegal, Near Glen, Donegal, . High Glen, Donegal, . Glen Lough, Donegal, Barnesbeg, Donegal, . Sheskinarone, Dungloe, Donegal. Gweebara Valley, Donegal, . S.E. of Lough Lagha, Donegal, M'Swire's Gun, Donegal, Keeloges, Church Hill, Donegal, S. of Lough Finn, Donegal, Malin Head, Donegal, St. Johnstown, Donegal, N, of Convoy, „ N. of Raphoe, „ Barnesmore, Donegal, Kildress, Tyrone, Anagarry, Donegal, Recarson, Tyrone, Sentrybox Hill, near Pomeroy, Tyrone, S.E. of Sentrybox Hill, Tyrone, Torr Head, Antrim, . 8. of Cushendall, Antrim, . ij Ji II ■ • 4 miles W. of Killyleagh, Down, N.W. of Downpatrick, Down, One-inch Map. 154 144 144 144 143 143 143 143 144 144 144 153 153 142 155 175 4 5 10 10 10 10 15 15 9 4 10 15 1 17 17 17 24 26 9 9 33 34 34 8 14 14 49 49 149 Index — continued. Reg. No. Locality. One-inch Map. 2357 Doo Glen, N. of Castlewellan, Down, . 48 2358 2 miles S.W. of 60 2362 24 !) ,! >, 60 2363 SlieveGarranl near „ ,, 60 2364 60 2366 Slieve Donard, Down, 60 2367 2 miles N.N.W. of Annalong, Down, . 61 2371 Mourne Mountains, Down, 60 2375 Glasdrumman, Down, . 61 2376 Arthur's Court, N. of Annalong, Down, 61 2386 Bath Lodge, N.E. of Ballycastle, Antrim, 8 2388 S.E. side of Fair Head, Antrim, . 8 2389 Fair Head, Antrim, 8 2395 Murlough Bay, Antrim, 8 2396 Tieveragh Hil], IST.W. of Cushendall, Antrim, 14 2401 2}j miles S.E. of Glenarm, Antrim, 20 2402 Slemish Mt., Antrim, . ' . 20 2403 ScawtHill, 4 miles S.S.E. of Glenarm, Antrim, 20 2404 )) ); n )» 20 2405 :! !) )) >' 20 2410 Carnearny Hill, Antrim, .... 28 2418 S.sideofCarnmoney Hill, near Belfast, Antrim, 28 2419 V )? J7 31 " 28 2420 ,; ,j -1 >J 1) 28 2425 N. of Garrickfergus, Antrim, 29 2429 Giant's Causeway, Antrim, 7 2435 Ballyemon Glen, near Cushendall, Antrim, 14 2436 M'Aulay's Head, Antrim, 20 2441 S. of Glenarm, Antrim, .... 20 2442 Browndod Hill, Antrim, 28 2444 Shane's Castle, Antrim, .... 28 2445 Cave Hill Quany, Belfast, .A.ntrim, 28 2447 S.E. of Carrick-a-Raidhe, Antrim, 7 2449 JJ JJ 3) ■ • 7 2450 2 miles N.E. of Templepatrick, Antrim 28 2455 Tardree, Antrim, 28 2458 Sandy Braes, Antrim, ... 28 2459 )) J) j» • • • * 28 2460 )) )) J) • ... 28 2463 Templepatrick Quarry, Antrim, 28 2464 >t J) 31 • • 28 2466 Giant's Causeway, Antrim, 7 2467 1 mile S. of Glenarm, Antrim, . 20 2469 N. of Slemish, Antrim, .... 20 2470 Clifford's Monument, Carrow, Roscommon, . 66 150 Index — continued. Beg. No. Locality. One-inch Map. 2471 Tawnytaskin, BoscGramon, .... 66 2472 )J )3 • * • 66 2473 N. of Boyle, „ . . . . 66 2472 Tawnytaskin, Curlew Hills, Roscommon, 66 2473 N. of Boyle, 66 2474 5^ iTiiles N.E. of Boyle, Koacommon, 66 2475 Rock of Doon, Roscommon, 66 2477 Moygara Castle, Sligo, 66 2478 E.S.E. Tawnyinah Upper, Mayo, 76 2479 N.N.W. of Tawnyinah Lower, Mayo, . 76 2481 W. Store Killala Bay, Mayo, . 53 2482 Carnanoiile, Castlebar, ,, . . 75 2483 Castlebar, Mayo, . . . . 75 2485 3 miles N.N.E. of Castlebar, Mayo, . 75 2487 Blacksod Bay, Mayo, ..... 51 2489 Near Goolamore Lodge, Mayoj 52 2490 Erris Head, Mayo, ... 39 2491 J) )j J) • • * 39 2492 Clare Island, „ . . . 73 2496 N.N W. of Leckanry Chapel, Mayo, . 74 2500 Carkeen, near Toormakeady, ,, 85 2502 CuMn, Galway, ... 83 2503 Omey, „ 93 2504 Claddaghduff, Omey, Galway, 93 2504a Lough Atalia, Galway, 93 2511 Keelkyle, Galway, 93 2512 Inisbofin, Mayo, 83 2513 Mullaghglass, Galway, 83 2514 Anghrusmore, Galway, 93 2517 Laghtanabba, „ . . 93 2521 Sea Shore, Galway, (35/3) . 93 2523 Gregg Quarries, Galway, 93 2526 Derryclare, Galway, ..... 94 2528 Lurgan Galway,'. . ... 94 2538 Leam East, Galway, ... 94 2540 Lettercraffroe, Galway, .... 105 2541 Doon, Galway, 105 2542 6 miles E. of Glendalough, Galway, 94 2544 Lough Shindilla, Galway, .... 94 2548 Glentrasna, Galway, ..... 104 2550 Shannaunafeola, Galway, .... 94 2553 Knockaphreaghaun, Galway, 94 2561 6 miles E. of Gtendalough-, Galway, 94 2563 Leam East, Galway, ..... 94 2567 Glentrasna, Galway, ..... 104 151 Index — continued. Bag. No. Locality. One-inoli Map. 2568 SbanuaduUaghaun, Galway, 104 2570 Bunnagippaua, Galway, 105 257 L Denny, E. of Lough Corrib, Mayo, 95 2572 Gortacurra, Mayo, 95 2576 Cannaver Island, L. Corrib, Galway, . 95 2577 „ South, L. Corrib, Galway, 95 2578 „ Lough Corrib, Galway, 95 2579 >j ji )) 95 2580 Shanballymore, Galway, 95 2596 Spiddal, Galway, ..... 105 2598 Near Minaunmore 1 Galway, 114 2601 Trusky West, Galway, .... 105 2603 Ahaglugger, Galway, 105 2606 Ballymuntermally, Galway, 105 2607 Rinville, Galway, . . . . 105 2609 Galway, (94/1) ... . . 105 2610 Townpark, Galway, 105 2611 J) J) • • • • 105 2615 Drum, Galway, 105 2616 Gortatle, Galway, ... 105 2617 Corboley Lynch, Galway, 105 2623 Furbogh 1 Galway, 105 2624 Cappagh, Galway, .... 105 2626 Forramoyle, Galway, .... 105 2628 Barna, opposite Coast Guard Station, Galway, 105 2631 Shantallow, Galway, 105 2640 New Dock, Galway, 105 2643 Cappanaveagh, Galway, 105 2645 Galway, (94/1) 105 2647 Stripe, Galway, .... 105 2649 Trusky West, Galway, 105 2650 )> »?•••• 105 2652 Town Park, „ ■ ■ ■ 105 2655 a )) • • 105 2659 t> 11 ■ ■ 105 2660 )j >J 105 2662 Bray Head, Wicklow, 121 2663 )) )j ■ • ■ 130 26.64 Bishop's Hill, near Blessington, Kildare, 120 2667 Ardbrackan Quarry, Navan, Meath, . 91 2669 1 mile N.E. of Graigue na-managh. Carlo w. 157 2670 Polmounty, near New Ross, Wexford, 157 2676 Three Rock Mountain, Dublin, . 112 2678 Dalkey, Dublin, ... 112 2679 Ballybrack, Dublin, 112 152 Index — continued. Eeg. No. Locality. One-inch Map. 2685 Graigue-na-managh, Carlow, 151 2686 W. side of Ballinacarrig, Wicklow, 130 2688 Near Kaheenavine House, Wicklow, : 139 2700 TaraHiin? Wexford, 149 2701 Tinnacarrick, Wexford, 169 2708 Wexford, .... . . 158 2709 ,, .... 158 2710 Caliore Point, Wexford, 149 2711 Red Cross, Wicklow, ..... 130 2716 Tincurry, S.W. of Ferns, Wexford, 148 2718 Driimgold, S.E. of Ennisoorthy, Wexford, . 158 2725 Ballinclare, Dunganstown, Wicklow, . 130 2726 Ti-Clash, Wicklow, .... 130 2728 Greystones, Wicklow, 121 2732 Croaghan Hill, Phiilipstown, King's County, 109 2733 )) )) J5 )) )? 109 2734 Croaghan Demesne, [?S.E. of Gorteen], PMllipstown, King's County, 109 2735 Croaghan Demesne, [% S.E. of Gorteen], Phiilipstown, King's County, 109 2737 N. of Baily Light House, Howth, Dublin, 112 2739 Lambay Island, Dublin, 102 2740 N. end of Heathtown, Meath, 92 2742 Starinagh .'! Meath, 81 2744 Carlingford, Louth, 71 2745 Slieve Foye, Carlingford, Louth. . 71 3753 Valentia Island, Kerry, .... 182 2755 Cod's Head, Cork, . . . , 191 2759 ,» 51 .... 191 2762 Tillickafinna, Dursey Island, Cork. 197 2765 W. side of Crow Head, Cork, 198 2767 W. point. Blackball Head, Cork, 198 2768 JJ 5) ')'»••• 198 2769 )j j> '5 '; 198 2772 Near Clogher Head, Kerry, 171 2774 Clogher Head, Kerry, 171 2776 Beginish Island, Kerry, 171 2777 )) J) »?•■•• 171 2778 S.W. of Anascaul, Kerry, . 172 2779 Stoompa Mountain, Kerry, 184 2780 N. slope of Stoompa Ridge, Kerry, 184 2782 N. side „ „ „ 184 2783 Near Head of Glen Plesk, „ 185 2789 Crumlin River, Antrim, .... 36 2790 ,) )> ;i ■ . . . 36 153 Index — continued, Reg. No. Locality. One-inch Map. 2792 2796 2801 2803 2805 2806 2813 2815 2817 2820 2825 2827 2830 2834 2836 2849 2853 2855 2856 2857 2869 2880 2861 2868 2870 2873 2874 2875 2877 2880 2881 2882 2885 2887 2890 2893 2895 2897 2898 2901 2902 2903 2906 W. of Siimny Lough, Donegal, . Gweebara Valley, Donegal, Glenieragli, Donegal, . Lough Salt, „ . , . N.E. of Tamney, Donegal, . Bloody Foi-elaud, „ Curvyfree Hill, Derry, Clondermot, Derry, Tirinisk, near Castlefinn, Donegal, Kildress, Tyrone, Rue Bane Point, Antrim, . Culfeightrin (Cushendun), Antrim, Cushendun, Antrim, . River Dall, Cushendall, Antrim, I mile S. of ,, „ Dillon, S.E. of Downpatrick, Down, Tullynasoo Mountain, Slieve-na-Largy, near Castlewellan, Down, Drtimkeer, Deerpark, S. of Newcastle, Down. Near Newcastle, Down, Glasdrumman, Down, Annalong, Down, PortrusL, Antrim, J) jj ". ' ' Oarnmoney Hill, Antrim, Giant's Causeway, Antrim., 3 miles N.E. of Ballymena, Antrim, Sandy Braes, Antrim, Connor, Sandy Braes, Antrim, . Browndod Hill, Antrim, Tempi epatrick, Antrim, >> ;) • • Ballaghaderin Area 1 Mayo, Ox Mountains, Sligo, 1 Belmullet, Mayo, 4 mile S.W. of Lough Nafooey, Mayo, Near Slieve Mahanagh, Mayo, . Near Bundorragha, N. of Killary Bay, Mayo, Bundorrragha, Mayo, ... W. of Culfin, Galway, Gannoughs Seashore, Galway, Lough Kippaun, E. of Waterloo Bridge, Olifden, Galway, ... 15 15 10 10 4 9 17 17 25 26 8 14 14 14 14 49 60 61 61 Gl 61 7 7 28 7 20 28 28 28 28 28 28 76 54 51 94 84 84 84 84 83 9? 93 ' 154 Index — continued. One-incli Eeg. No. Locality. Map. 2908 Lettery, Galway, 94 2910 Near Maum, Galway. 94 2911 Glencraif, Galway, 94 2912 94 2914 Learn East, Galway, . 94 2916 W. end of Lough Shindilla, Galway, 94 2920 Learn East, Galway, . 94 2921 S. of Lough Braiiu, Mayo, . - 2923 Killaqnile, Galway, 105 2924 Lettercraffroe, Galway, 105 2925 Roundstone, Galway, . 103 2927 Cappagh, Galway, 105 2930 Barna, 5 miles W.S.'W. of Galway, 105 2933 Einmore, Galway, 105 2940 Cappanaveagh, Galway, 105 2941 Dangan Upper, Galway, 105 2942 Spiddal, Galway, 105 2943 Shantallow, Galway, ... 105 2944 Attithomasrevagb, Galway, 105 2952 Near Bingham Castle, Mayo, 51 2666 Letterbeg, Blacksod Bay, Mayo, . 51 2999 Glencastle Bridge, .Mayo, . 52 3018 S.E. of Portnacally, „ 51 3023 >J U )J • • 51 3262 Slishwood Gap, Lough Gill, Sligo, 55 3330 Newry, Down, .... 60 3440 JST. side Howth, Dublin, 112 3441 )) >} jj • • 112 3442 ti »j a • • 112 3443 jj )) )j • • 112 3444 Glendalough, Wicklow, 130 3445 Round wood, ,, . . 130 3452 Glendalough, „ . . ' . 130 3453 jj ,^ ■ . . 130 3454 » n ... 130 3456 Dingle, Kerry, . ... 171 3457 Duuquin, „ 171 3458 )!!>•• • . 171 3459 J) )? • • • 171 3461 Clogher Head, Kerry, 171 3463 Dunquin, Keny, .... 171 346T „ Dingle, Keiry, . 171 3469 Knockaunavoher, Tipperary, 154 3470 Clinoe Cottage, near Limerick, . 144 155 Index — continued. Eeg. No. Locality. O»e-inoli Hap. 3472 3474 3473 3475 3476 3477 3478 3480 3481 3485 3518 3519 3523 3543 5546 3547 Head of Ballyemon Glen, near Cushendall, Antrim, .... K Ireland? Above Carrick-a-Eaidhe, Antrim, Antrim, ..... Carrig-na-Miick, Wioklow, Faby, King's County, Shore under Killiney Hill, Dublin, Termonmaquirk, Athenree, Tyrone, The Schal], Altmover Glen, Derrr, Clogher Head, Louth, 14 7 130 110 112 34 34 18 82 82 82 82 82 82 Dublin : Printed for Her Majesty's Stationery Office, By Alex. THOM & Co. (Limited), 87, 88, & 89, Abbey-street, The Queen's Printing Office. 163. 7. 96, 2000. s >yi