'^^^y^^ rjsMi THE FOOD OF THE SHORE FISHES OF CERTAIN WISCONSIN LAKES : : : : By A. S. Pearse From BULLETIN OF THE BUREAU OF FISHERIES, Volume XXXV, 191 5-1 6 Document No. 856 : : : : : : Issued January 9, 1918 PWCE, 10 CEWTS Sold only by the Superintendent of Documents, Government Printing Office, Washington, D. C WASHINGTON :::::: GOVERNMENT PRINTING OFFICE WortpoTsplt 1 T. eaTS>e-j MvTi^j_^ »■ p'^yVM , i'VT7 THE FOOD OF THE SHORE FISHES OF CERTAIN WISCONSIN LAKES : : : : By A. S. Pearse From BULIyETIN OF THE BUREAU OF FISHERIES, Volume XXXV, 191 5-1 6 Document No. 856 : : : : : : : : ; ; ; ; ; ; Issued January 9, igi8 PRICE, 10 CENTS Sold only by the Superintendent of Documents, Government Printing Office. Washington, D. C. WASHINGTON ::::;; GOVERNMENT PRINTING OFFICE 9^ > D, of D. FEB 8 1918 A. CONTENTS. I. Introduction 249 II. Description of foods 251 Abramis cr\soleucas; bream, golden shiner 251 Ambloplites rupestris; rock bass, goggle-eye 252 Ameiurus melas; black bullhead 253 Ameiurus nebulosus; speckled bullhead 254 Amiatus calva; bowfin, grindle 254 Boleosoma nigrum ; johnny darter 255 Catostomus commersonii; common sucker 256 Cottus ictalops; miller's thumb 256 Cyprinus carpio; carp 257 Esox lucius; pickerel 258 Etheostoma flabellare; fan-tailed darter 259 Etheostoma iowae; Iowa darter 259 Eucalia inconstans; brook stickleback 259 Eupomotis gibbosus; pumpkinsced 260 Fundulus diaphanus menona; menona top minnow 261 Labidesthes sicculus; brook silversides 262 Lepisosteus osseus; long-nosed gar 263 Lepomis incisor; bluegill, blue suniish 264 Micropterus dolomieu; smallmouth black bass 266 Micropterus salmoides; largemouth black bass 266 Notropis heterodon; shiner 267 Perca flavescens; yellow perch 269 Percina caprodes; log-perch _ 270 Pimephales notatus; blunt-nosed minnow 271 Pimephales promelas; blackhead minnow; fathead 272 Pomoxis sparoides; black crappie 272 Roccus chrysops; white bass 273 Salmo irideus; rainbow trout 274 Salvelinus fontinalis; brook trout 274 Schilbeodes gyrinus; tadpole cat 274 Stizostedion vitreura; wall-eyed pike 275 Umbra limi; mud minnow 275 III. Foods utilized by fishes 276 Different species of fishes have specific food habits 276 Classes of foods utilized by fishes 277 IV. Adaptability of food habits 279 Alternative foods 279 Variation in food of fishes collected in different loc alities and at different times 280 Variation in food at different periods of the life cycle 280 V. Influence of food on the selection of habitats 281 VI. General considerations on the food of the shore fishes of lakes . . . . ' 282 Bibliography 291 247 i THE FOOD OF THE SHORE FISHES OF CERTAIN WISCONSIN LAKES. By A. S. PEARSE, University of Wisconsin. I. INTRODUCTION. Since the excellent work of Forbes (1880, 1883, 1888) in the eighties no thorough study has been made of the food of fresh-water fishes in the United States. The data for the present paper were collected during 1914, 1915, and 1916 near Madison, Wis. They relate primarily to the shore fishes of lakes, though the food habits of many from other habitats were studied. Small fishes were more often examined than large, because their food habits are less well known. During the first year 383 fishes were examined; during the second, i,iii; and in the third, 125. The summaries for 191 4 have already been published (Pearse, 191 5). Collections were made at 30 different stations, which are shown in the chart. They may be described briefly as follows: 1. Lake shore at Merrill Springs. A small stream enters a little bay; three large springs flow directly into the lake; shore, sandy and pebbly. 2. Lake shore near Pheasant Branch. Muddy, weedy bottom in mouth of creek; pebbles and a little sand on either side. 3. Lake shore at Maypest. Sandy in shallow water; weedy and soft mud farther out. 4. Six-Mile Creek at fork. Bottom very soft mud; current sluggish. 5. Mouth of Six-Mile Creek. Bottom very soft mud; weedy. 6. Bar across mouth of Catfish Bay. Bottom pebbly. 7. Yahara River above Catfish Bay. Bottom soft mud; current sluggish. 8. Lake shore at Farewells Point. Bottom stony. g. Small bay near State Insane Asylum. Bottom clay, with water plants. 10. Lake shore in bay. Bottom sandy and pebbly in shallow water; firm mud with weeds in deeper water. 11. Lake shore at Maple Bluff. Beach of rocks and pebbles from the cliff above. 12. Pebble beach east of Maple Bluff. 13. Small bay choked with vegetation; bottom very soft nijid. 14. Pebbly beach at mouth of Yahara Canal. 15. Lake in front of University of Wisconsin. In shallow water, sand and bowlders; in deeper water, mud and vegetation followed by soft ooze. 16. Southeast end of University Bay behind bar. Bottom soft mud; abundant vegetation, both floating and attached. 17. Beach outside bar on east side of base of Picnic Point. Bottom pebbly and sandy in shallow water; muddy with weeds at greater depths. Behind bar, soft mud and much vegetation. 18. Beach along southeast side of Picnic Point. Bottom pebbly in shallow water, then sandy, and in deeper water muddy with thick vegetation. 19. Beach northwest of Picnic Point. Bottom of pebbles or sand. 849 250 BULLETIN OF THE BUREAU OF FISHERIES. 20. Small spring pools on the north shore of Lake Wingra. Bottom soft mud with abundant vege- tation. 2 1. Small creek on south side of Lake Wingra. Bottom clay and mud. 22. Muddy bottom near outlet of Lake Wingra. 23. Yahara Canal, connecting Lake Mendota \Wth Lake Monona. Bottom muddy with thick vegetation; pebbles along shores. 24- Pebble and sand beach on southwest shore of Lake Monona. mud Thirty stations wliere collections were made 25. Swamp behind Chicago, Milwaukee and St. Paul Railroad near Lake Monona. 26. TurviU Bay. Bottom very soft mud with considerable vegetation. 27. Pebble and sand beach near mouth of Lake Monona. 28. Vegetation filled bay at outlet of Lake Monona. Bottom sand and mud 29. Catches from power seines of commercial fishermen in Lake Waubesa 30. Brook near State fish hatchery, 4 miles south of Madison. Bottom clay, stones, and verj- soft i. FOOD OF THE SHORE FISHES OP CERTAIN WISCONSIN LAKES. 25 1 Collections were made with a miniature fyke net, dip net, minnow seine, and gill net. When thev could not be examined within an hour or two, the fishes were placed in 95 per cent alcohol and kept until examined. In examining the food, the entire contents of the alimentary canal were pressed out on a strip of glass, moistened, and then teased apart with needles under a binocular microscope. Insect fragments were turned over to an expert entomologist for identification. As the constituents of the food were identi- fied, they were written in the permanent record. As each fish was completed, the per- centage by volume of each constituent was estimated. All figures in this paper refer to such volumetric percentage estimates. During the work assistance was rendered by a number of persons, and it is a pleasure to acknowledge this indebtedness. Dean E. A. Birge and Mr. Chancey Juday, of the Wisconsin Geological and Natural History Survey, loaned equipment and extended other courtesies. Miss Henrietta Achtenberg worked four months computing averages and rewrote part of the manuscript. Dr. John Lowe and Mr. Alvin Cahn furnished some rare fishes for examination. Mr. A. F. Shira and Mr. Juday read the manuscript and made a number of helpful suggestions. Invaluable assistance was rendered by Dr. R. A. Muttkowski, who identified all the insects. II. DESCRIPTION OF FOODS. All figures following foods are given in volumetric percentages ; + indicates a trace. The lengths are given in millimeters and exclude the caudal fin. The species are arranged alphabetically according to their scientific names. Under each species the records are arranged according to dates, and the stations (see chart) where collections were made are given in each case. Abramis crysoleucas (MitchiU). Golden shiner, roach, bream. Station 5; August 18, 1915; number examined, 2. Length: Maximum, 94; minimum, 92.5; average, 93.2. Food: Hyalella, 42.5; Bosmina, 0.5; Camptocerus, 1.5; filamentous algae, 40.5; fine silt and debris, 15- Station 5; August 18; number examined, 5. Length: Maximum, 31.3; minimum, 23.5; average, 28.1. Food: Helea larva, i; Tanypus cameus larva, 4; insect, 3; water mites, 1.2; ostracods, 4; Cyclops, 2^; Canthocamptus, 2; Cladocera unidentified, 14; Bosmina, 14; Pleuroxus, 1.4; Chydorus, 3; Simoce- phalus, 7; rotifers, 0.8: plant tissue, 4.8; seeds, 0.8; Wolffia, 3; Volvox, 2.2; Closterium, 0.4; Pandorina, 0.4. Summary.— Food: Dipterous larvae, 5; insects, 3; water mite, 1.2; ostracods, 4; copepods, 35; Clado- cera, 39.4; rotifers, 0.8; plants, 8.6; flagellates, 3. Station 18; August 18; number examined, 23. Length: Maximum, 75; minimum, 34; average, 39.3. Food: Tanypus monilis pupae, 12.4; Cyclops, 20; Daphnia longispina hyalina, 65; Simocephalus, 2.1. Station 5; August 25; number examined, 10. Length: Maximum, 68; minimum, 27.5; average 33.2. Food: Chironomus lobiferus larvae, 5.5; water mites, 2; Cyclops, 0.2; Bosmina, 88.5; Ceriodaphnia, 3.5; algal filaments, o.i; Volvox, o.i. Station22; April I, i9i6;numberexamined, I. Length; 152. Food: Caddis-fly case, 0.5; ostracods, 90; Cyclops, 0.5; Daphnia pulex, i; filamentous algae, 8. Summary. — Insect larvae, 0.5; Entomostraca, 91.5; plants, 8. Station 18; April 13; number examined, 3. Length: Maximum, 137; minimum, 114; average, 122.6. Food: Larvae sp., 6.6; Chironomus sp. larvae, 2.3; C. lobiferus larvae, 0.3; Orthocladius flavus larvae, 0.3; Copotomus interrogatus adult, i; Chironomus sp. adult, 38.3; Hyalella, 15; Cyclops, i; snail remains, 1.6; Valvata tricarinata, 15; Lemna, 15; debris, 3.3. Summary.— Food: Insect larvae, 9.5; adult insects, 39.3; amphipods, 15; copepods, i; MoUusca, 16.6; plants, 15; debris, 2-2- 252 BULLETIN OF THE BUREAU OF FISHERIES. Station 22; April 22; number examined, 10. Lengtli; Maximum, 133; minimum, 112; average, 123.4. Food: Chironomus decorus larvae, 3.5; Chironomus sp. larvse, 2; Cricotopiis trifasciatus larvae, 2.6; May-fly nymphs, 2; chironomid pupae, i; Cricotopus trif;isciatus pupae, 1.5; Hyalella, o.i; ostracod, 0.2; Canthocamptus, 1.5; Cyclops, 33.8; Daphnia pulex, 19.3; Chydorus sphaericus, 5.1; Bosmina, 1.5; Physa, 2; Oscillatoria, 4.7; flagellates, 0.2; Volvox, 0.7; plant remains, 9; algae, o.i; fine debris, 9.1. Sumtnary. — Food Insect larvae, 10. i; insect pupae, 2.5; amphipods, 0.1; Entomostraca, 61.4; Mol- lusca, 2; Protozoa, 0.2; plants, 14.5; d6bris, 9.1. Station 22; June 10; number examined, 5. Length: Maximum, 150; minimum, 115; average, 125. Food; Ostracods, 0.1; Daphnia pulex, 99.9. Grand summary for iQij and igi6. — Number examined, 59. Length: Maximum, 152; minimum, 23.5; average, 67.6. Food: Insect larvae, 4.4; insect pupae, 5.7; adult insects, 2.2; mites, 0.4; amphipods, 2.2; Entomostraca, 76.1; rotifers, +; protozoans, i; plant remains, 3.1; algae, 1.5; debris, 2.2. From these summaries it is apparent that the chief food of the golden shiner was microscopic crusta- ceans (76.1 per cent). More than half the food of 10 of the fish consisted of other organisms — 81 per cent filamentous algae, 85 per cent Hyalella, 55 per cent Chironomus lobiferus larvae, 51 per cent silt and fine debris, etc. AH other individuals had eaten 50 per cent or more Entomostraca; some had eaten nothing but Daphnia or Bosmina. Forbes and Richardson (1908) state that the food of this species varies greatly in different situations and mention mud, molluscs, insects, entomostracans, and plants as appearing in the dietary. Hankinson (1908) found midge larvae and filamentous algae in the fish he examined. The fish examined by Baker (1916) had eaten a small percentage of molluscs, and about 97 per cent insects, chiefly caddis-fly larvae. Considering all things, it appears that when young the golden shiner feeds chiefly on entomostracans, and mature fish on almost any available organisms. Ambloplites rupestris (Rafinesque). Rock bass, red-eye, goggle-eye. Data for 1914 (Pearse, 1915). — Number examined, 5. Average length: 61.4. Food: Insects, 68; mites, 0.4; Hyalella, 5.6; ostracods, i; Cladocerans, 15; plants, 4; algae, 0.2; silt and debris, 0.4. Station 15; May 27, 1915; number examined, i. Length; 99. Food; Chironomus fulviventris larvae, 3; C. decorus larvae, 10; Procladius sp. larvae, 10; Molanna uniophila larvae, 69; Ecdjoirus maculi- pennis nymphs, 2; Chironomus fulviventris pupae, 5; Valvata tricarinata, i. Summary. — Food: Chironomid larvae, 23; caddis-fly larvae, 69; May-fly larvae, 2; chironomid pupae, 5; snail, I. Station 15; June 9; number examined, I. Length; 115. Food; Siphlurus nymph, 2; Chironomus fulviventris pupa, 3; water mite, 0.5; crayfish, 94.5. Station 5; June 24; number examined, I. Length: 188. Food; Enallagma hageni and E. anten- natum nymphs, 10; Cambarus propinquus, 90. Station 15; July 24; number examined, i. Length: 168. Food: Cambarus propinquus, 100. Station 18; July 3; number examined, 19. Length; Maximum, 81; minimum, 35.6; average, 53.6. Food: Chironomus lobiferus larvs, 0.7; C. digitatus larvae, i; Cricotopus trifasciatus larvae, 3.1; Pal- pomyialongipcnnislarvas, 23.1; Leptocerusdilutus larvae, 2.7; Ichythricha larva, 0.1; damsel-fly n)'mphs, 4.2; Rcdyurus maculipennis nymphs, 0.7; Enallagma hageni nymphs, 2.7; E. antennatum nymphs, 25; caterpilUu-, i; Chironomus lobiferus pupae, 5.4; Palpomyia longipennis pups, 5; same, adult, 11. 4; Corixa, 0.7; mites, 0.6; ostracods, 0.3; Eiu^'cercus, 7.6; oligochaetes, 2.6; filamentous algae, i. Summary. — Food; Dipterous larvae, 27.9; caddis-fly larvae, 2.8; damsel-fly nymphs, 32.6; cater- pillar, i; dipterous pupae, 10.4; adult insects, 12. i; mites, 0.6; ostracods, 0.3; cladocerans, 7.6; oligochaetes, 2.6; algae, i. Station 23; June 14; number examined, I. Length; 45.5. Food: Chironomus tenellus larvae, 100. Station 23; July 23; number examined, 5. Length: Maximum, 99; minimum, 61; average, 76.8. Food: Chironomus fulviventris lar\'ae, 17.4; Palpomyia longipennis larvae, 0.4; Caenis diminuta nymphs, 8.5; Enallagma antennatum nymph, 7; pamid beetle larva, i; Chironomus fulviventris pupae, 23; Tany- pusmonilis pupae, 1.8; Palpomyia longipennis pupae, 0.4; Probezzia pallidapupa, 5; Simulium vittatum pupa, 1.8; Corixa adults, 2; Berosus, 3.4; Agabus, 2; Haliplus ruficoUis, 2.6; crayfish, 12.4; Hyalella, 6; oligochxtes, 3; seeds, 0.2; Elodea, 2. Summary. — Food: Dipterous lar\-ae, 17.8; caddis fly larvae, 8.5; damsel fly nymphs, 7; beetle larva, i; dipterous pupae, 32; adult insect, 10; craj-fish, 12.4; Hyalella, 6; oligochaetes, 3; plants, 2.2. Station 23; August 19; number examined, i. Length: 66. Food: Carabid-beetle larva, 2; insect remains, 3; plant remains, 75; sand, 20. FOOD OF THE SHORE FISHES OF CERTAIN WISCONSIN LAKES. 253 Station 18; August 18; number examined, i. Length: 59. Food: Chironomus viridis larvje, 20; Baetisca nymphs, 20; Chironomus lobiferus pupae, 60. Station 23; August 19; number examined, i. Length: 22.5. Food; Chironomus lobiferus larvae, 75; Cyclops, 10; oligochfetes, 15. Station 10; August 20; number examined, 2. Lengths: 31.5, 29. Food: Labidesthes sicculus, 45; Chironomus lobiferus larvae, 2.5; Chironomus digitatus larvae, 12.5; Baetisca nymphs, 40. Station 23; September 21; number examined, i. Length: 109. Food: oligocha:tes, 50; plant remains, 20; sand and mud, 30. Station 15; September 25; number examined, i. Length: 112. Food: Cambarus propinquus, 100. Station 15; November 20; number examined, 2. Lengths: 160, 121. Food: Labidesthes sicculus, 42.5; Baetis nymphs, 2.5; Sialis infumata larva, 50; Chironomus lobiferus pupae, 5. Station 25; December 4; number examined, i. Length: 230. Food: Crayfish, 100. Grand summary for IQ14 and IQIS- — Number examined, 45. Length: Maximum, 230; minimum, 22.5; average, 72.9. Food: Fish, 2; dipterous larvs, 19. i; May-fly nymphs, 3.5; Odonata nymphs, 14.4; caddis-fly larvae, 2.8; Sialis infumata larvae, 2.2; beetle larvae, 0.5; unidentified insect larvae, 0,5; dipter- ous pupae, 9.6; Diptera, 4.8; Hemiptera, 1.2; Hymenoptera, 1.3; Coleoptera, i.i; unidentified insects, 5.3; hydrachnids, 0.2; crayfish, 16. i; amphipods, 1.4; ostracods, 0.3; copepods, 0.3; cladocerans, 4.3; gastropods, -\-; oligochaetes, 3; plant remains, 2.8; algae, 0.5; silt and debris, 1.2. The summaries show that the food of the young rock bass consists largely of insects (larvae, 43 per cent; pupae, 9.6 per cent; adults, 13.7 per cent), which constitute more than three-fourths of the food. The adult fish feed mostly on crayfish, though they also capture insects in considerable numbers. Forbes and Richardson (1908) state that this bass eats insects, small crustaceans, and a few fish. Han- kinson ( 1908) found that it fed chiefly on crayfish, with smaller percentages of dragon-fly nj-mphs, midge larvae, small fishes, and May-fly nymphs. Reighard (1915) found fish, insects, and crayfish in those he examined. According to Baker (1916) about three-quarters of the food is Crustacea and the remainder plants, algae, insects, and debris. Ameiurus melas (Rafinesque). Black bullhead. Data for igi4 (Pearse, 1915). — Number examined, 2. Length: Maximum, 123; minimum, 38.2; average, 80.6. Food: Dipterous larvae, 40; Diptera, 2.5; ostracods, 12; Cyclops, 2.5; unidentified clado- cerans, i; Bosmina, 25; plant remains, 17.5. Station 5; August 18, 1915; number examined, i. Length: 274. Food: Enallagma hageni nymphs, 2; Gyrinus larva, 6; dytiscid larva, 2 ; Leptocerus larva, 3; Phryganea interrupta larva, 5; caterpillar, 20; Chironomus fulviventris pupa, 16; Chironmus fulviventris adult, 11; Enallagma hageni adult, 13, Psychoda adult, i; Corixa adult, 10; crayfish claw, i; Hyalella, i; leech, 5; Lemna, 3. Summary. — Food: Insect larvae, 38; insect pupae, 16; adult insects, 35; crayfish, i; Hyalella, i; leech, 5; Lemna, 3. Station 5; September 14; number examined, i. Length: 275. Food: Chironomus decorus larvae, 30; C. lobiferus larvje, 20; C. digitatus larvae, 5; Enallagma hageni nymphs, 5; Chironomus decorus pupa, 30; C. lobiferus pupa, 8; Hyalella, 2. Summary. — Food: Dipterous larvae, 60; dipterous pupae, 38; Hyalella, 2. Station 28; September 17; number examined, i. Length: 280. Food: Probezzia glaber larvae, 4; P. pallida larvae, 4; Tipula abdominalis larva, i; Planorbis, 25; Physa, 30; plants, 10; Lemna, i; Nostoc, 15; silt and debris, 10. Summary. — Food: Dipterous larvae, 9; snails, 55; plants, 26; silt and debris, 10. Station 16; September 20; number examined, 10. Length: Maximum, 190; minimum, 35; average, 79.3. Food: Chironomus decorus larvae, 6.3; C. fulviventris larvae, 10; C. tentans larvae, 0.5; Chironomus sp. larvae, 11. 5; Protenthes culiciformis larva, o.i; Probezzia glaber larvae, 1.6; P. pallida larva, 4.5; Chironomus decorus pupae, 0.6; C. fulviventris adults, 5.4; crayfish, 9.2; Cyclops, 0.5; leech, 4; oligo- chaetes, 32.1; plants, 4.7; silt and fine debris, 8.5. Summary. — Food: Chironomid larvae, 24.5; chironomid pupae, 0.6; chironomid adults, 5.4; crayfish, 9.2; Cyclops, 0.5; leech, 4; oligochaetes, 32.1; plants, 4.7; silt and debris, 8.5. Grand summary for IQ14 and igiS- — Number examined, 15. Length: Maximum, 280; minimum, 35; average, 118. 8. Food: Dipterous larvae, 32.6; damsel-fly nymphs, 0.4; beetle larvae, 0.4; caddis-fly larvae, 0.5; caterpillar, 1.3; dipterous pupx, 4.2; adult insects, 5.7; Hyalella, 0.2; crayfish, 6.1; ostracods, 104848=— 18 2 254 BULLETIN OF THE BUREAU OF FISHERIES. 1.6; Cyclops, 0.7; cladocerans, 0.5; snails, 3.7; leech, 3; oligochastes, 21.4; plants, 6.4; algae, 0.9; silt and d6bris, 6.3. The food of the black bullhead, according to the summary, contains 45.1 per cent insects (larvae, 35.2; pupae, 4.2; adults, 5.7) and 21.4 per cent oligochaetes. Young fish apparently eat more oligo- chsetes than adults. Forbes and Richardson (1908) examined 34 individuals of this species and found the food to be one-foiutli plants, and one-fifth bivave molluscs, snails, aquatic insects, crayfishes, and other crustaceans. Ameiurus nebulosus (Le Sueur). Common bullhead, bro^Ti bullhead, speckled bullhead. Station 5; May 21, 1915; number examined, 16. Length: Maximum, 94; minimum, 54.5; average, 64.7 Foqd: Unidentified insect larvae, i; Chironomus decorus larvae, 0.2; C. viridicoUis larvae, i; C. f ulviventris larvae, 0.9; C. tentans larvae, 8.6; C. lobiferus larvae, 5.2; Helea larva, 0.3; Cricotopus trifascia- tus larvae, 7.1; Ptychoptera larva, i; May-fly nymphs, 0.6; Callibsetis nymphs, 0.7; beetle lar\'a, 1.2; carabid-beetle larva, 0.3; unidentified pupa, 0.3; Probezzia pupa, 0.6; unidentified insect fragments, 2.2; midges, o.i; mites, 1.2; Hyalella, 0.6; ostracods, 21; Cyclops, 11; Chydorussphaericus, 22; Eur>-cercus lamellatus, 2; Ceriodaphnia, o.i; cladoceran ephippia, 0.7; snail, 0.5; plants, 2.3; sand and fine debris, 7.3. Summary. — Food: Insect larvae, 28. i; insect pupae, 0.9; adult insects, 2.3; mites, 1.2; ostracods, 21; Cyclops, 11; cladocerans, 24.8; snail, 0.5; plants, 2.3; silt and debris, 7.3. Station 6; June 24; number examined, i. Length: 86. Food: Palpomyia longipennis larvae, 10; Callibaetis nymphs, 5; Caenis diminuta nymphs, 10; Enalfagma hageni nymphs, 25; fragments of adult insects, 50. Station 5; August 9; number examined, 33. Length: Maximum, 47.6; minimum, 25; average, 36.2. Food: Unidentified chironomid larvae and cases, 2.8; Chironomus fulviventris larvae, 5; C. lobi- ferus larvae, 6.3; Protenthes culiciformis larvae, 7.3; Probezzia glaber larvae, 1.3; P. pallida larvae, 0.6; Baetis nymphs, 2 ; Enallagma hageni nymphs, 1.3; insect pupae, 0.8; chironomid pupae, i; Chirono- mus lobiferus pupae, 6; adult midges, 2.3; Anax Junius, 0.2; gj-rinid beetle, 0.5; Collembola, 0.5; mites, 0.1; Hyalella, 18; ostracods, 2; Cyclops, 6; Bosmina, 0.1; Chydorus sphaericus, 9; Emycercus, 0.3; Camptocercus, 17; Pleuroxus procurvatus, 4; Acroperus, 0.5; Ceriodaphnia, 1.6; Scapholeberis, 0.3; oligochaetes, 4.7. Summary. — Food: Insect larvae, 26.6; insect pupae, 7.8; adult insects, 3.4; mites, 0.1; Hyalella, 18; ostracods, 2; Cyclops, 6; cladocerans, 32.3; oligochaetes, 4.7. Grand summary. — Number examined, 50. Length: Maximum, 94; minimum, 25; average, 46.3. Food: Insect larvae, 28.2; dipterous pupae, 2.1; adult insects, 4.4; mites, 0.4; amphipods, 11.4; ostra- cods, 6.7; copepods, 8.4; cladocerans, 33.1; snails, 0.1; oligochaetes, 2.1; rotifers, -f; protozoans,-!-; plants, 0.9; algae, -f-; silt and debris, 2.3. Of the food of this bullhead 42.1 per cent consists of microscopic Crustacea, 34.7 per cent of insects. It apparently feeds more on Entomostraca than the black bullhead. Forbes and Richardson (1908) found the food to consist chiefly of small bivalve molluscs, insect larvae, distiller}^ slops, and a few adult insects and snails. Hankinson (1908) states that this species is an omnivorous feeder, taking cra;>'fish, fish, molluscs, entomostracans, leeches, beetles, May-fly and dragon-fly nymphs. Tracy (1910) found "all kinds of animal life," including the young and eggs of fishes. Reighard (1915) records small fishes and a bumblebee as food. Crustaceans formed the chief food of the young individuals examined by Baker (1916), while the older fish had eaten 10 per cent MoUusca and 90 per cent vegetation and mud. The brown bullhead feeds mostly on Entomostraca and insect larvae while it is young, and when mature takes almost anything in the shape of animal food. Amiatus calva (Linnaeus). Bowfin", grindle. Station 17; August 24, 1915; number examined, i. Length: 545. Food: Crayfishes, 100. Station 28; September 14; number examined, 6. Length: Maximum, 438; minimum, 383; average, 406. Food: Fish remains, 37.5; Lepomis incisor, 59.3; crayfish, 3. Station 28; September 17; number examined, 4. Length: Maximum, 543; minimum, 388; average, 470. Food: Fish remains, 48.5; sunfish, 43.5; crayfish, 7.5. Station 22; July i, 1916; number examined, 3. Length: Maximum, 465; minimum, 440; average, 452.6. Food: Fish remains, 96.6; crayfish remains, ^.t,. Summary. — Food: Fish remains, 96.6; crayfish remains, 3.3. o X,ocaUy known as dogfish. FOOD OF THE SHORE FISHES OF CERTAIN WISCONSIN LAKES. 253 Station 22; July 8; number examined, i. Length: 420. Food; Fish remains, 100. Station 22; July 15; number examined, i. Length, 412. Food: Fish remains, 100. Summary/or igis and I(ii6. — Number examined, 16. Length: Maximum, 465; minimum, 383; average, 467.4. Food; Fish remains, 90.1; crayfish remains, 9.4. It will be observed that no young dogfish were examined. Forbes and Richardson (1908) examined 20 fish and foimd the food to be entirely animal — one-third fishes, one-fourth small molluscs, and about 40 per cent crayfishes. A few amphipods, isopods, and entomostiacans were also noted (Forbes, 1883). Boleosoma nigrum (Rafinesque). Johnny darter. Station 14; July 9, 1915; number examined, i. Length, 15. Food: Cricotopus trifasciatus larvse, 10; oligochaetes, 55; Cyclops, 20; Chydorus, 15. Station 5; August 18; number examined, i. Length, 30. Food: Helea larvs, 15; Tanypus car- neus larvK, 25; May-fly nymphs, 10; oligochaetes, 15; ostracods, 15; Chydorus, 20. Station ig; August 18; number examined, 10. Length; Maximum, 34.5; minimum, 23; average, 28.7. Food: Tanypus monilis larvte, 2.4; Chironomus digitatus larvae, 53.3; C. viridis larvte, 2.4; C. lobiferus larvs, 2.5; C. tentans larvae, 1.5; Ecdyurus maculipennis nymphs, 6.5; C. digitatus pupse, 1.5; oligochaetes, 15; Hyalella, 2.8; Cyclops, 4.7; Chydorus, 1.3; Pleuroxus, + ; Ceriodaphnia, 1.6; sand, 4.7. Summary. — Food: Chironomid larvae, 63.1; May-fly nymphs, 6.5; chironomid pupse, 1.5; oligo- chaetes, 15; amphipods, 2.8; copepods, 4.7; cladocerans, 2.9; sand, 4.7. Station 19; August 20; number examined, 20. Length; Maximum, 32; minimum, 21.5; average, 27.5. Food: Probezzia pallida larvae, 0.7; Tanypus monilis larvae, 1.2; Chironomus digitatus larva, 46; C. viridis larvae, 3.5; C. lobiferus larvae, 8.1; Leptocerus dilutus larvae, 0.2; C. digitatus pupa, 2; adult midge, 0.2; oligochsetes, 22.4; mite, +; Hyalella, 0.2; ostracods, 0.2; Cyclops, 8.1; Chydorus, o.i; Pleuroxus, -f ; Ceriodaphnia, 1.5; Eurycercus, 0.7; Daphnia, i; sand, 1.9. Sum-mary. — Food: Chironomid larvae, 59.5; caddis-fly larvae, 0.2; chironomid pupte, 0.2; adult midge, 0.2; oligochaetes, 22.4; mites, +; amphipods, 0.2; ostracods, 0.2; copepods, 8.1; cladocerans, 0.4; sand, 1.9. Station 10; August 20; number examined, i. Length; 30. Food: Chironomus digitatus larvae, 20; oligochaetes, 42; Hyalella, 10; Cyclops, 15; Chydorus, 3; Ceriodaphnia, 10. Station 12; August 20; number examined, i. Length: 32.5. Food; Chironomus digitatus larvae, 60; Hyalella, 30; Eurycercus, 10. Station 5; August 25; number examined, i. Length, 38.2. Food; Chironomus digitatus larvae, 47; C. lobiferus larvae, 40; oligochaetes, 5; ostracods, 3; Cyclops, 5. Station 5; August 30; number examined, i. Length: 41.3. Food: Chironomus lobiferus larva, 10; Protenthes culiciformis larvae, 10; oligochaetes, 47; Cyclops, 30; diatoms, 3. Station 14; August 31; number examined, 3. Lengths: 41, 36.5, 29; average, 35.6. Food; Chiron- omid larva, 5; Cricotopus trifasciatus larva, 2.3; Chironomus digitatus larvae, 35; C. viridis lar\-ae, 2.3; Protenthes culiciformis larvae, 2.3; mites, 0.3; Hyalella, 15; Cyclops, 8; Chydorus, 18; sand, 10. Summary. — Food: Chironomid larvae, 46.9; mites, 0.3; amphipods, 15; copepods, 8; cladocerans, 18; sand, 10. Station i; September i; number examined, 10. Length: Maximum, 48.5; minimum, 27.5; average, 34.9. Food: Cricotopus trifasciatus larvae, 1.4; Chironomus digitatus larvae, 41.5; C. viridis larvae, i.i; C. lobiferus larvae, 7.4; C. tentans larvae, 3.5; Corethra larvae, 0.2; Ca-nis diminuta nymphs, 0.5; C. digitatus pupae, 1.5; oligochaetes, 13.7; Hyalella, 13.9; Cyclops, 5; Chydorus, o.i; Pleuroxus, 0.2; Eurycercus, 6.3; cladoceran, 0.1; sand, 3.5. Summary. — Food: Chironomid larvae, 55.1; May-fly nymphs, 0.5; chironomid pupae, 1.5; oligo- chaetes, 13.7; amphipods, 13.9; copepods, 5; cladocerans, 6.7; sand, 3.5. Station 5; September 2; number examined, 2. Lengths: 41, 31. Food : Insect eggs, 2 . 5 ; Probezzia pallida larvae, 11; Chironomus digitatus larvae, 5; C. lobiferus larvae, 45.5; C. tentans larvae, 21.5; adult midge, 0.5; oligochaetes, 5; Cyclops, 5; cladoceran, i; sand, 3. Summary. —Food: Chironomid larvae, 85.5; midge, 0.5; oligochaetes, 5; copepods, 5; cladocerans, i; sand, 3. Grand summary. — Number examined, 50. Length: Maximum, 48.5; minimum, 21.5; average, 30.9. Food: Insect larvae, 59.2; insect pupae, 1.4; adult insects, 0.1; oligochaetes, 18.4; amphipods, S-i; ostracods, 0.5; copepods, 7.4; cladocerans, 5.6; diatoms, -f; sand, 3.1. 256 BULLETIN OF THE BUREAU OF FISHERIES. The chief food of the Johnny darter is chironomid larvae, with oligochates forming the second largest item. Forbes and Richardson (1908) stated that tlie food of the fish they examined consisted of two-thirds chironomid larvae, 12 per cent small May flies, and 7 per cent gnat larvse. Hankinson (1908) reported chiefly midge larvse, with some filamentous algae and Entomostraca. Reighard (1915) found midge larvae and entomostracans. Catostomus conunersonii (Lac^pedc). Common sucker, fine-scaled sucker. Station 24; July 2, 1915; number examined, 23. Length: Maximum, 24.3; minimum, 13; aver- age, 19.9. Food: Chironomus lobifcrus eggs, o.i; C. lobiferus lar\-ae, 5.2; C. digitatus larvae, 5.6; C. viridis larvae, 1.3; C. flavus larvae, 1.3; C. tentans larvae, 2.4; Cricotopus trifasciatus larvae, 41.3; C. tentans pupae, 3.4; bug, -|-; midge, 0.3; ostracods, 17.5; Cj'clops, 3.7; Cladoceran, 2.2; Bosmina, i.i; Chydorus, 1.5; Eiuyxercus, -|-; oligochaetes, 13.5; rotifers, o.i; Closterium, +; Pediastrum, -f; diatoms and desmids, -f; Aphanothece, 0.1. Summary. — Food: Chironomid lar\'ae, 55.9; chironomid pupae, 3.4; adult insects, 0.3; ostracods, 17.5; copepods, 3.7; cladocerans, 3.9; oligochaetes, 13.5; rotifers, i; Protozoa, +; algae, 0.1. Station 5; August 25; number examined, 6. Length: Maximum, 60; minimum, 38.5; average, 47.9. Food: Chironomus lobiferus larvae, 0.5; Probezzia glaber larvae, 0.8; ostracods, 12.3; Cj'clops, 48.4; cladocerans, 0.3; oligochaetes, 7; Arcella, 0.1; Difflugia, 8.5; Closterium, 1.6; desmids and di- atoms, 2.5; fine silt and d6bris, 16.9. Summary. — Food: Chironomid lar\'ae, 1.3; ostracods, 12.3; copepods, 48.4; cladocerans, 0.3; oligo- chaetes, 7; protozoans, 8.6; algae, 4.1; silt and debris, 16.9. Station 5; August 30; number examined, 3. Length: 58, 53.6, 44; average, 51.8. Food: Chiron- omus lobifcrus lar\'3e, 4; Corethra adult, 2.3; I>>'tiscus, 2.3; mite, -)-; ostracods, 27; Cyclops, 14; chydorid, 6.3; oligochaetes, 10; rotifers, 1.3; Arcella, 0.3; Difflugia, i; Closterium, 10.3; desmids and diatoms, 14; silt and debris, 4.3. Summary. — Food: Chironomid larvae, 4; adult insects, 4.6; ostracods, 27; copepods, 14; cladoc- erans, 6.3; oligochaetes, 10; rotifers, 1.3; protozoans, 1.3: algae, 24.3; silt and debris, 4.3. Station 5; September 2; number examined, i. Length: 44. Food: Enallagma eggs, 25; Cyclops, 56; Chydorus, 1; oligochaetes, 10; rotifers, i: Difflugia, i; desmids and diatoms, i; silt and debris, 5. Grand summary. — Number examined, 34. Length: Maximum, 60; minimum, 13; average, 29.2. Food: Insect eggs, 0.7; chironomid larvae, 40.6; chironomid pupae, 2.4; adult insects, 0.6; mites, 0.1; ostracods, 16.8; copepods, 14.8; cladocerans, 3.6; oligochaetes, 11. 5; rotifers, 0.2; Protozoa, 1.3; algae, 3; silt and debris, 3.6. The common sucker when young feeds mostly on chironomid larvae (40.6 per cent), entomostracans (35.2 per cent), and oligochaetes (11. 5 per cent). Tracy (1910) described the young as feeding on di- atoms, desmids, and black-fly larvae; the adults on insects, worms, molluscs, young fishes, and fish eggs. Reighard (1915) found that the yoimg ate mostly cladocerans, 2,000 being foimd in one individual. He told how the adults mouth over plants from one end to the other, and stated that they ate the eggs of the log perch. Hankinson (1908) found the food of adults to consist of caddis-fly lar\^ae and cases, Sphaeridae, amphipods, insects, marl, midge larvae, and Daphnia. Baker (1916) reported his examina- tions as follows: Mud and plant remains, 49 per cent; molluscs, 30 per cent; insecta, 21 per cent. The sucker is remarkable for the fineness of the food it is able to select. No other fish shows such a high percentage of protozoans, unicellular algae, and rotifers in its food. Cottus ictalops (Rafinesque). Miller's thumb, common sculpin. Data for igi4 {Pearsc, 1915). — All from station 11; number examined, 10. Average length, 45. Food: May-fly nymphs, 66; chironomid larvae, 7.1; adult midge, 1.5; Hyalella, 13.5; ostracods, 0.5; C>'clops, 1.5; leech, 9; filamentous algae, 0.9. Station 14; July 9, 1915; number examined, 2. Lengths: 21.7, 20.5. Food: Cricotopus adults, 7.5; Hyalella, 60; ostracods, 2.5; C>xlops, 10; chydorid, 2.5; oligochaetes, 10; filamentous algae, 7.5. Station 23; July 23; number examined, i. Length: 57.5. Food: Chironomus fulviventris larvae, 10; Diamesi waltii larvae, 10; Hyalella, 60; oligochaetes, 15; plant remains, 5. Station 19; August 18; number examined, i. Length: 31. Food: Chironomus lobiferus larv-ae, 40; Hyalella, 60. Station 19; August 20; ni'.mber examined, 2. Lengths: 33, 32.5. Food: Chironomus digitatus larvae, 21.5; Hyalella, 75; samd, 3.5. FOOD OF THE SHORE FISHES OF CERTAIN WISCONSIN LAKES. 257 Station 19; August 30; number examined, 2. Lengths: 33.5, 41. Food : Hyalella, 96 ; oligochaetes, 4. Station 19; August 31; number examined, 2. Lengths: 30.5, 30.5. Food: Chironomus digitatus larvffi, 10; C. viridis larvse, 10; Caenis diminuta nymphs, 8.5; Hyalella, 68.5; Cyclops, i; oligochaetes, 0.5; sand, 1.5. Station 14; August 31; number examined, i. Length: 35.5. Food: Chironomus digitatus larvae, 10; Baetisca nymphs, 30; Hyalella, 60. Station i; September i; number examined,!. Length: 35. Food: Chironomus digitatus larvK, 5; Baetisca nymphs, 15; Hyalella, 80. Station 11; September 2; number examined, 5. Length: Maximum, 46; minimum, 31.5; average, 40. Food: Chironomus digitatus larvae, 0.4; Heptagenia interpunctata larvae, 0.6; Hyalella, 98; ostra- cods, I. Station 11; September 11; number examined, 2. Lengths: 49, 39. Food: Hyalella, 95; ostracods, i; Nostoc, 4. Station i; October 2; number examined, i. Length: 48. Food: Dikerogammarus fasciatus, 100. Grand summary for 1(114 a^id jQi;.— Number examined, 30. Length: Maximum, 57.5; minimum, 20.5; average, 39.6. Food: Chironomid larva, 7.5; caddis-fly larvje, o.i; May-fly nymphs, 24; adult midges, i; amphipods, 59.1; ostracods, 0.6; copepods, 1.2; cladocerans, o.i; oligochaetes, 0.7; leeches, 3; plant remains, 0.1; algae, i; sand, 0.2. The miller 's thumb subsists mostly on amphipods and insect larvae. It evidently Ivirks under stones and rushes out to capture small things which swim by. Forbes and Richardson (1908) examined six individuals, and 25 per cent of the food consisted of small fishes, 40 per cent of insect larvae, and the remainder mostly Asellus. They also stated that this fish was said to be very destructive to the eggs and fry of trout. Cyprinus carpio Linnaeus. German carp. Station 23, in a little inland pool connected with Yahara Canal by a ditch; July 12, 1915; number examined, 4. Length: Maximum, 21.7; minimum, 18; average, 20.1. Food: Unidentified chironomid larvae, 5.2; Probezzia pallida larvae, 2.5; Tanytarsus agrayoloides larvae, 10; G>Tinus larvae, 2.5; Dytiscus hybridus larvae, 2.5; Diamesi waltii larvae, 4.2; D. waltii pupae, 2.7; Palpomyia longipennis pupae, 0.7; Leptocella uwarowii adult, 17.5; CoUembola, 2.5; ostracods, 28.7; Cyclops, 2.5; Chydorus 1.2; roti- fers, 13.7; colonial algae, 0.7; desmids, 0.2; Wolffia, 2.5. S^lmmary.— Food: Chironomid larvae, 21.9; beetle larvae, 5; chironomid pupa, 3.2; adult insects, 20; ostracods, 28.7; copepods, 2.5; cladocerans, 1.2; rotifers, 3.7; plants, 2.5; algae, 0.9. Station 5; August 9; number examined, 18. Length: Maximum, 64; minimum, 15; average, 31.8. Food: Helea larvae, 0.8; Chironomus fulviventris larvae, 7; C. lobiferus larvae, 2; Cricotopus trifasciatus larvse, 0.3; Probezzia pallida larvae, 0.8; May-fly nymphs, 0.8; Caenis diminuta nymphs, 3; Berosus larvae, 0.3; Haliplus larvae, 0.1; Corixa nymph, 2.7; Palpomyia longipennis adults, 0.3; C. fulviventris adults, 2.5; Corethra adults, 2.5; Dytiscus adults, 2.5; Hyalella, 16.3; ostracods, 9.4; Cyclops, 14; Can- thocamptus, 0.5; mites, 1.7; Ceriodaphnia, 1.4; Chydorus, 3.7; Camptocercus, 0.8; Pleuroxus, 0.7; un- identified cladocerans, 0.8; ephippial eggs, 0.5; unidentified snalis, 6.4; Physa, 1.6; Planorbis, 2; oli- gochffites, 6.3; Pleurococcus, 1.4; Wolffia, 4.7; plant remains, 1.6. Summary. — Food: Insect larvae, 17.7; adult insects, 7.8; mites, 1.7; Hyalella, 16.3; ostracods, 9.4; copepods, 14.5; cladocerans, 7.9; snails, 9; oligochffites, 6.3; algae, 1.4; plants, 6.3 Station 23, in a little inland pool connected with Yahara Canal by a ditch; August 11; number ex- amined, 18. Length: Maximurri, 44.6; minimum, 21; average, 29.5. Food: Insect eggs, 0.6; Chironomus fulviventris larvae, 53.1; C. lobiferus larvae, 5; C. tentans larva, 2.5; Palpomyia longipennis larvae, 0.5; May -fly nymphs, i; Canis diminuta nymphs, 4. 9; Naucoris larva, 0.1; Chironomus fulviventris pupa, 7.2; adult insects, i; Haliplus maculatus adults, 1.5; Chironomus fulviventris adults, 0.3; Corethra adults, 1.5; mites, 2.8; ostracods, 0.3; Cyclops, 8.9; Ceriodaphnia, 0.3; Chydorus, 0.5; Cladoceran, 0.1; snails, 0.8; Physa, 0.8; Planorbis, 4.3; rotifers, -f ; Difflugia, +; filamentous alga, 0.3; plant remains, 0.2; silt, 0.3. Summary.— Food: Insect lar\-a, 67.6; insect pupa, 7.2; adults, 4.3; mites, 2.8; ostracods, 0.3; cope- pods, 8.9; cladocerans, o.g; snails, 5.9; rotifers, +; protozoans, 4-; alga, 0.3; plants, 0.2; silt, 0.3. Station 28; September 14; number examined, i. Length:46o. Food: Chironomid larva, i;ostracods, i; Cyclops, 2; plant remains, 61; duckweed, 7; blue grass, 8; fine silt and debris, 20. 258 BULLETIN OF THE BUREAU OF FISHERIES. Station 22; April 22, 1916; number examined, i. Length: 120. Food: Chironomid sp. Iar%'aB, 30; ostracods, 4.8; Cyclops, 24; chydorid, o.i; Chydorus, o.i; plant remains, i; bottom debris, 40. Summary. — Food: Insect larvse, 30; Entomostraca, 29; plants, i; debris, 40. Grand summary for igis and igi6. — Number examined, 42. Length: Maximum, 460; minimum, 15; average 41.7. Food: Insect larvse, 39.7; insect pupse, 6.8; adult insects, 3.3; mites, 1.8; amphipods, 6.9 ; entomostrpcans, 20.9 ; snails, 6.9; oligochsetes, 2 .8 ; rotifers, i . i ; protozoans, + ; algae, 0.8 ; plant remains, 4.9; silt and d6bris, 1.5. The German carp during its first few weeks after hatching from the egg feeds largely on entomos- tracans and rotifers; after that it turns more to insect larvae. The adult carp is rather omnivorous, but vegetation forms a large part of its food. Forbes and Ricliardson (1908) stated that tlie carp eats princi- pally vegetable matter, also insect larvje, crustaceans, molluscs, and other small aquatic animals. Tracy (1910) said it is omnivorous and chiefly vegetarian in its diet. Cole (1905) stated that the food was mostly vegetable and mentioned many other things he found, including the eggs of whitefish. Esox lucius Linnaeus. Common pike, pickerel. Station 17; April 17, 1915; number examined, i. Length: 730. Food: Micropterus salmoides (165 mm. long), 55; Perca flavescens (160 mm.), 45. Station 17; April 25; number examined, i. Length: 765. Food: Perca flavescens (185 mm.), 100. Station 15; June 12; number examined, i Length: 164.5. Food: Perca flavescens (95 mm.), 100. Station 23; July 23; number examined, i lella, 95. Station 15; June 26; number examined, i. Station 15; August 7: number examined, i. ridae, 10. Station 15; August 21; number examined, i. 100. Station 17; August 23; number examined, 2. mm., 105 mm.), 100. Station 17; August 24; number examined, i nymphs, 4; Naucoris larvae, 4; ephippial eggs, 2. Station 28; September 17; number examined, - age, 487. Food: Small sunfish, 50; fish remains, 50 Station 29; November 16; number examined, 2. mm.), 50; fish remains, 50. Station 22; April i, 1916; number examined, i. Station 18; April 13; number examined, 4 217.5. Food: Fish remains, 100. Station 18; April 17; number examined, i. fish remains, 100. Station 18; April 18; number examined, 2. 50; leech, 50. Station 27; May 30; number examined, 2. notatus, 50; Perca flavescens, 50. Station 18; June 29; number examined, i. Station 18; June 12; number examined, i. 20; Caenis diminuta nymphs, 30. Station 18; July 7; number examined, 2. Food: Fish remains, 50; Perca flavescens, 50. Station 17; July 10; number examined, 6. Length: Maximum, 100; minimum, 81; average, 88.8. Food: Micropterous salmoides, 66.6; Perca flavescens, 16.6; Caenis diminuta nymphs, 10; midge pupae, 6.6. Grand summary for igi^ and igi6. — Number examined, 36. Length: Maximum, 876; minimum, 45; average, 293.4. Food: Fish, 84; insect larvae, 2.9; insect pupae, i; adult insects, 2.5; amphipods, 2.5; Entomostraca, 2.6; Hirudinea, 2.5; Mollusca, p.2; silt and debris, 1.2. Length: 143. Food: Diamesi waltii adult, 5; Hya- Lcngth: 420. Food: Fish remains, 100. I. Length: 155.5. Food: Fish remains, 90; Sphae- Length: 587. Food: Perca flavescens (134 ram.). Lengths: 362, 400. Food: Perca flavescens (140 Length: 317. Food: Fish remains, 90; Corixa (. Length: Maximum, 555; minimum, 455; aver- Lengths: 876, 563. Food; Perca flavescens (200 I. Length: 233. Food: Fish remains, 100. Length: Maximum, 238; minimum, 200; average. Length, 227. Food: Notropis heterodon and other Lengths: 293, 203; average, 248. Food: Chydorus, Lengths: 320, 295; average, 305. Food: Pimephales Length: 220. Length: 45. Food: Fish remains, 100. Food: Minnow, 50; chironomid lar\'£e. Length: Maximum, loo; minimum, 90; average, 95. FOOD OF THE SHORE FISHES OF CERTAIN WISCONSIN LAKES. 259 The small pickerel apparently eats a few insects and molluscs; the adults live nearly altogether on fish. Other observers have found the food to be as follows: Forbes and Richardson (1908)— fishes and frogs, cra>^ishes, larger insects, and occasionally even mice, reptiles, and young ducks; Hankinson (1908) — perch, darters; Rcighard (1915) — perch and fish remains. Etheostoma flabellare Rafinesque, var. lineolatum Jordan and Evermann. Fan-tailed darter. Data Jor IQ14. — Station 11; September 4; number examined, 2. Lengths: 29.6, 31.3. Food: Chironomid larvae, 75; adult midge, 0.5; Hyalella, 24.5; Camptocercus, +. Station 19; December 3; number examined, i. Length: 38.7. Food: Chironomus lobiferus larvae, 35; C. viridis larvae, 40; Hyalella, 25. Station 23; July 12, 1915; number examined, i. Length: 48.3. Food: Hyalella, 80; oligochEetes, 15; plant remains, 5. Station 14; August 31; number examined, i. Length: 38.7. Food: Agraylea raultipunctata larvae, 13; Hyalella, 86; chydorid, i. Grand summary for JQ14 and IQIJ. — Number examined, 5. Length: Maximum, 48.3; minimum, 29.6; average, 37.3. Food: Chironomid larvae, 42; caddis-fly larvae, 4.8; adult midge, 0.2; Hyalella, 48; cladocerans, 0.2; oligochaetes, 3; plant remains, i. The fan-tailed darter lives mostly on chironomid larvae and amphipods. Forbes and Richardson (1908) examined six fish and found two-thirds chironomid larvae, one-fotuth May-fly nymphs, and the remainder copepods. Etheostoma iowae Jordan and Meek. Iowa darter. Station 23; July 9, 1915; number examined, 4. Length: Maximum, 55; minimum, 45.5; average, 48.5. Food: Unidentified chironomid larvae, 12.5; Chironomus fulviventris larvae, 11. 2; C. tentans larvae, 2.5; Berosus larvae, 9; Gyrinus larvae, 11. 2; Hyalella, 47.5; Physa heterostropha, 3.7; olio-o- chaetes, 2; fine dtfbris, 0.5. Station 23; August 31; number examined, i. Length: 45. Food: Hyalella, 100. Graiid summary. — Number examined, 5. Average length, 47.8. Food: Chironomid larvae, 21; beetle larvae, 16; amphipods, 58; snails, 3; oligochaetes, 1.6; fine debris, 0.4. This beautiful little darter subsists nearly altogether on amphipods and insect larva. Eucalia inconstans (Kirtland). Brook stickleback. Datafor IQ14 (Pearse, 1915). — Number examined, 50. Length: Maximum, 48.5; minimum, 22; average, 31.7. Food: Dipterous larvae, 13.2; May-fly nymphs, 1.4; Corixa nymphs, +; caddis-fly larvae, 1.3-, unidentified adult insects, 2.2; midges, 13.6; podurans, 0.7; mites, 0.5; Hyalella, 0.2; os- tracods, 3.6; copepods, 28.5; cladocerans, 14.9; snails, 6.3; Sphaeridae, o.i; oligochaetes, 0.3; nematodes, + ; rotifers, -f; Difflugia, -f ; plants, 5.4; algae, 1.7; fine debris, 4.6. Station 21; April 28, 1915; numberexamined, 10. Length: Maximum, 51; minimum, 30.1; average, 40.6. Food: Chironomid larvae, 2.5; Pelopia flavifrons larvae, 1.5; Chironomus fulviventris larvae, 2; C. flavus larvae, 3; C. lobiferus larvae, 0.6; C. modestus larvae, 0.2; C. digitatus larvae, 0.2; Tanytarsus dissimilis larvae, 0.2; Orthocladius sp. larvae, 0.7; Cricotopus exilis larvae, 0.4; Cricotopus trifasciatus pupae, 0.2; Chironomid adults, 3.8; Hyalella, 11. 5; Dikerogammarus fasciatus, 15.2; young amphipods, 5.5; ostracods, 5; Cyclops, 12; Canthocamptus, i; oligochaetes, 7.3; rotifers, 4.3; diatoms, +; algae, 0.5; filamentous algae, 0.2; gelatinous algae, 0.5; plant remains, 8.5; silt and fine debris, 16.6. Summary. — Food: Chironomid larvae, ri.3; chironomid pupae, 0.2; adult midges, 3.8; amphipods, 32.2; ostracods, 5; copepods, 13; oligochaetes, 7.3; rotifers, 4.3; algae, 1.2; plants, 8.5; silt and dt^bris, 16.6. . Station 20; April 28; number examined, 10. Length: Maximum, 44; minimum, 31; average, 40.6. Food: Fish eggs and embryos, 2.5; Pelopia flavifrons larva, 0.3; chironomid larvae, 0.9; C. flavus larvae, 0.7; C. lobiferus larvae, 0.7; C. dorsalis larvae, 0.2; C. tentans larvae, 0.6; C. viridicoUis larva, 0.2- Tanytarsus exiguus lan'ae, 3.4; Orthocladius nivoriundus larvae, 0.9; adult midge, 0.5; insect, 1.5; Asellus communis, 14; Dikerogammarus fasciatus, 3; ostracods, 3.7; Cyclops, 16.8; Canthocamptus, 7.3; Qhydorus sphaericus, 32.2; Physa, 7.5; Physa eggs, i; oligochates, i; filamentous alga, o.i; silt and debris, 0.6. Summary. — Food: Chironomid larvae, 10.4; adult insects, 2; amphipods, 17; ostracods, 3.7; cope- pods, 21. i; cladocerans, 32.2; snails, 8.5; oligochaetes, i; algae, 0.1; silt and debris, 0.6. 26o BULLETIN OF THE BUREAU OF FISHERIES. Station 20; June 12; number examined, 30. Length: Maximum, 43.5; minimum, 9.4; average, 19.1. Food: Caddis-fly larvae, i.i; chironomid larvae, 7.1; Chironomus tentans, 8.9; psychodid larvae, 0.3; Tanj-tarsus cxiguus larvae, 6.4; Orthocladius sp. larvae, 0.5; O. nivoriundus larvae, 0.8; Cricotopus, exilis larvae, 1.9; C. trifasciatus larva, 5; C. trifasciatus pupae, 11. 4; Chironomus tentans pupae, 17.3; C. fulviventris pupx, +; Aedes adults, i; leaf hopper, i; ostracods, 2.5; Cyclops, 4.8; Canthocamptus, 1.5; nauplii, o.i; Chydorus sphaericus, 20; Ccriodaphnia, 0.9; rotifers, 4.3; diatoms, o.i; filamentous algae, 0.1; plant remains, 0.1. Summary. — Food: Chironomid larvae, 30.9; caddis-fly larvae, i; chironomid pupae, 28; adult in- sects, 2; ostracods, 2.5; copepods, 6.4; cladocerans, 20.9; rotifers, 4.3; algae, i.i; plants, 0.1. Station 21; June 12; number examined, 6. Length: Maximum, 42; minimum, 30; average, 37. Food: Chironomid larva;, 0.2; Chironomus fulviventris larvae, 64.6; Tanytarsus exiguus lar\-ae, 4.3; Chironomus fulviventris pupae, 20; Aedes adults, 5.8; Hyalella, 3.6; Cyclops, 1.3; amphipods, 3.6; copepods, 1.3. Summary. — Food: Chironomid larvae, 69.1; chironomid pupae, 20; adult mosquitoes, 5.8; amphi- pods, 3.6; copepods, 1.3. Station 25, from a ditch beside the road; July 2; number examined, 4. Length: Maximum, 28. 6; minimum, 13.2; average, 19.6. Food: Chironomid larva, 2.5; Tanj'tarsus exignus larva, 6.2; Tany- tarsus monilis larvae, 28.2; adult midge, 1.2; Hcrmannia bistriata, 11. 2; ostracods, 13.7; Cyclops, 22.5; Ceriodaphnia, 1.2; oligpchaetes, 7.2; rotifers, 4.7; diatoms, i; gelatinous algae, 1.2. Summary. — Food: Chironomid larva, 36.9; midge, 1.2; terrestrial mite, 11. 2; ostracods, 13.7; cope- pods, 22.5; cladocerans, 1.2; oligochates, 7.2; rotifers, 4.7; alga, 2.2. Grand summary for igi4 and igiS- — Number examined, no. Length: Maximum, 51; minimum 9.4; average, 29.3. Food: Fish eggs, 0.2; dipterous larva, 21.5; hemipterous larva, -f; May-fly larva, 0.6; caddis-fly larva, 0.9; chironomid pupa, 9.1; adult Diptera, 7.3; hemipterous adults, 0.3; podu- rans, 0.3; unidentified insects, i.i; mites, 0.6; amphipods, 3.4; Asellus, 1.2; ostracods, 3.2; copepods, 19.3; cladocerans, 16; snails, 3.6; Sphaerida, 0.1; oligochates, i.i; rotifers, i.i; nematodes, -f; alga, 1.2; plants, 3.2; silt and debris, 3.7. The brook stickleback ate over 41 per cent insects (lar\'a, 23: pupa, 9.1; adults, 9) and 38.5 per cent entomostracans. Forbes and Richardson (190S) examined five fish and found about equal parts of plant and animal food — filamentous alga, insects, chironomid larva, and entomostracans. Eupomotis gibbosus Linuaus. Pumpkinseed. Station 17; April 10, 1915; number examined, 3. Lengths: 155, 14S, 145. Food: Protenthes, choreus larva, 0.6; Chironomus fulviventris larva, 0.6; Enallagma hageni nymphs, 2.6; Sialis larva, 1.6; Colymbetis adults, 20; leeches, 8.3; Planorbis, 40; plant remains, 22.6; fine debris, ^.^. Station 17; April 13; number examined, 2. Lengths: 133, 126. Food: Toad eggs, 42.5; Planor- bis, 30; plant remains, 5; alga, 15; fine debris, 7.5. Station 28; August 19; number examined, i. Length: 116. Food : Chironomus lobiferus larva, 15; Chrysops larva, i; Chironomus lobiferus pupa, 2; Corixa adults, 5; Probezzia glaber, 3; Hyalella, 74. Station 28; August 24; number examined, 2. Lengths: 187, 142. Food: Micronecta nymph, 1.5; Caenis diminuta nymphs, 2.5; Enallagma antennatum nymphs, 0.5; Sialis larva, 2.5; Stratj'iomyia discalis larva, 2.5; Notonecta nymph, 3.5; Corixa adults, 4.5; Hyalella, 1.5; Physa, 1.5; sponge, 10; Lemna, 7.5; Ceratophyllum, 48.5. Station 15; October i; number examined, i. Length: 160. Food: Chironomus lobiferus larva, 35; Leptocella uwarowii adult, 10; Hyalella, 5; crajiish, 12; Valvata tricarinata, 10; Amnicola limosa, 10; Ancylus, 3; plant remains, 5; Vallisneria, 10; Myriophyllum, 2; filamentous alga, 3. Grand summary. — Number examined, 9. Length: Maximum, 187; minimum, 116; average, 145.7. Food: Toad? eggs, 9.4; insect larva, 11. 6; insect pupa. 0.9; adult insects, 9.3; amphipods, 9; cray- fish, 1.3; leeches, 2.8; snails, 25.8; sponge, 2.2; plants, 21.9; alga, 3.6; fine debris, 2.8. The food of the pumpkinseed was made up of insects (22.1 per cent), large Crustacea (10.3 per cent), snails (25.8 per cent), plants (25.5 per cent), and otlier things. Forbes and Richardson (1908) found tliat more than half the food of the fish they examined was molluscs; the rest was amphipods, isopods, and insects. Hankinson (190S) reported midge hu-va, May-fly nymphs, cra>'^ishcs, amphipods, snails, leeches, and caddis-fly lar\'a. Reighard (1915) found snails, insect larva, and Chara. Insects formed the chief food of those fish examined by Baker (1916). FOOD OF THE SHORE FISHES OF CERTAIN WISCONSIN LAKES. 261 Fundulus diaphanus men^La (Jordan and Copeland). Menona top minnow. Data for igi4 (Pearse, 1915). — Number examined, 49. Length: Maximum, 49.5; minimum, 27.5; average, 35.4. Food: Dipterous larvse, 6.1; beetle larvae, 0.6; hemipterous larvae, 0.7; dragon-fly nymphs, +; May-fly nymphs, 1.7; podiu'ans, -|-; insects, 3.2; mites, i; Hyalella, 16.2; ostracods, 25.2; copepods, 1.2; cladocerans, 27; Planorbis, o.i; plant remains, o.i; Wolfiia, 14.7; filamentous algae, 0.1. Station 17; December 3; number examined, i. Length: 37. Food: Chironomus viridicollis larvae, 5; C. viridis larvte, 5; Chydorus sphsericus, 10; Ceriodpalinia, 40; Eurycercus lamellatus, 40. Summary. — Food: Chironomid larvae, 10; cladocerans, 90. Station 19; December 3; number examined, i. Length: 38. Food: Cricotopus trifasciatus larvae, 92 ; Hyalella, 8. Station 17; April 6, 1915; number examined, 10. Length: Maximum, 42.1; minimum, 27.9; average, 31.6. Food: Dipterous larvae, 7; Chironomus tentans larva, 5.8; C. fulviventris larvae, 10; C. decorus larvae, 8; Corethra larvae, 6; adult Diptera, 14; ostracods, 6.5; Cyclops, 5.5; Canthocamptus, 2.5; Chydorus sphsericus, 4; oligochaetes, 14.3; nematodes, 0.2; unknovm eggs, 10; plants, 0.2; algae, 3; fine debris, 3. ^ Summary. — Food: Dipterous larvae, 36.6; adult Diptera, 14; ostracods, 6.5; copepods, 8; cladoc- erans, 4; oligochaetes, 14.3; nematodes, 0.2; unknown eggs, 10; plants, 3.2; fine debris, 3. Station 17; April 13; number examined, 4. Length: Maximum, 45.5; minimum, 30; average, 39.5. Food: Chironomid lar\'£e, 5; Chironomus fulviventris larvae, 0.5; C. decortis larvae, 0.9; C. lobiferus larvae, 14.2; ostracods, 15.5; Cyclops, 9.2; Canthocamptus, 3.7; Ceriodaphnia, -|-; oligo- chaetes, 3.7; nematodes, 1.2; plant remains, 4.2; Wolifia, 10.7; algae, 1.5; fine debris, 29.2. Summary. — Food: Chironomid larvae, 20.6; ostracods, 15.5; copepods, 12.9; oligochastes, 3.7; nematodes, 1.2; plants, 16.4; fine debris, 29.2. Station 21; April 28; number examined, 10. Length: Maximum, 46; minimum, 27; average, 38.6. Food: Young fish with yolk sacs, 6.g; chironomid larvae, 0.6; Chironomus fulviventris larvae, 3.6; C. flavus larvae, 2; Tanypus decoloratus larvae, 0.8; Tanytarsus exiguus larvs, 2 ; T. dives larvs, 2 ; Ortho- cladius sp. larvae, 0.4; O. nivorixmdus lar\'ae, 4; Palpomyia longipennis larvae, i; Tabanus larvae, i.i; podurans, 0.7; midges, 9.2; Dikerogammarus fasciatus, 19.7; Cyclops, 3.1; Canthocamptus, 1.3; Sphae- ridae, 4; oligochaetes, 1.5; eggs, i.i; plant remains, 7.2; fine debris, 17. i. Summary. — Food: Dipterous larvae, 17.5; adult insects, 9.9; amphipods, 19.7; copepods, 4.4; Sphaeridae, 4; oligochaetes, 1.5; eggs, i.i; plants, 7.2; fine debris, 17. i. Station 21, along shore of Lake Wingra; April 28; number examined, 10. Length: Maximum, 39; minimum, 33; average, 38. Food: Tanypus decoloratus larvae, 0.3; T. d. pupae, 16; Cricotopus trifasciatus pupae, i; adult Diptera, 0.5; terrestrial mites, 1.4; ostracods, 46.5; C>'clops, 15.7; Cantho- camptus, 1.5; Chydorus sphaericus, 5.1; Eurycercus, 8.1; nematodes, 0.3; algae, 3.5. Summary. — Food: Dipterous larvae, 0.3; dipterous pupae, 17; adult insects, 0.5; mites, 1.4; ostra- cods, 46.5; copepods, 17.2; cladocerans, 13.2; nematodes, 0.3; algae, 3.5. Station 5; May 12; number examined, 10. Length: Maximum, 59; minimum, 34; average, 47.4. Food: Fish eggs, 4.5; Cricotopus trifasciatus larvae, 4.4; Chironomus viridis larvae, i; C. viridicollis larvae, 5.6; Tanypus decoloratus lar\-s, 2.2; Pelopia monilis larvae, i; Orthocladius sordidellus larvae, 2.5; Probezzia pallida larvae, 0.1; Caenis diminuta nymphs, 6.4; May-fly nymphs, 0.5; Orthocladius sordidellus pupae, 2.4; Tanypus decoloratiis pupae, 0.8; Collembola, 0.5; midges, i; terrestrial mites, 0.8; Hyalella, 3.5; ostracods, 26.2; Cyclops, 5.8; Chydorus sphaericus, 21.2; Eurycercus lamellatus, 2.9; Sphaeridae, i; Planorbis, 1.2; plant remains, 0.7; algae, 1.3; fine debris, 0.5. Summary. — Food: Fish eggs, 4.5; insect larvae, 20.1; pupae, 3.2; adult insects, 1.5; mites, 0.8; amphipods, 3.5; ostracods, 26.2; copepods, 5.8; cladocerans, 25.1; molluscs, 2.2; plants, 2; fine de- bris, 0.5. Station 16; May 15; number examined, 8. Length: Maximum, 52; minimum, 32; average, 39.5. Food: Helea larvae, 2; Cricotopus trifasciatus larvae, 20.7; Tanypus decoloratus larvae, 0.5; Ortho- cladius sordidellus larvae, 5.5; Palpomyia larvae, 5; Caenis diminuta nymphs, 2.1; Cricotopus trifas- ciatus pupae, s; mites, 3; ostracods, 7; Cyclops, 18.5; Chydorus sphaericus, 2; Pleiu-oxus procurvatus, 1.5; Planorbis, 11. 7; oligochaetes, 12; plant remains, 0.2; algae, 0.1. Summary. — Food: Insect larvae, 35. 7; pupae, 5; mites, 3; ostracods, 7; copepods, 18.5; cladoc- erans, 3.5; snails, 11. 7; oligochaetes, 12; plants, 0.3. 104848°— 18 3 262 BULLETIN OF THE BUREAU OF FISHERIES. Station 5; June i; number examined, 10. Length: Maximum, 49; minimum, 30; average, 38. Food: Beetle larvae, 6; May -fly nymphs, i ; HelealarvEC, i; Chironomus decorus larvae, 2.7; C. lobiferus larvae, 4.8; Orthocladius sordidellus larvae, 37.7; Probezzla glaber larvae, 0.4; C. digitatus pupae, o.i; HyalcUa, 1.5; ostracods, 12.5; Cyclops, 0.5; Chydorus sphaericus, 3.3; Eurycercus, 5.7; snails, 0.5; Planorbis, 12.5; Limnaea, 9; Physa ,0.8. Summary. — Food: Insect larvae, 54.6; pupae, o.i; araphipods, 1.5; ostracods, 12.5; copepods, 0.5; cladocerans, 9; snails, 23.2. Station 6; June 24; number examined, 10. Length: Maximum, 58.8; minimum, 37; average, 48.4. Food: Helea larvae, 0.5; Chironomus plumosus larvae, 0.4; C. lobiferus lar\'ae, 1.2; Orthocladius sordidellus larvae, 0.5; Prob^zzia glaber larvae, 2; Ecdyurus maculipennis nymphs, 16.8; Orthocladius sordidellus pupae, 0.2 • Tanypus monilis pupae, 0.1; C. decorus pupae, 0.5; C. digitatus pupa, i; Corixa adults, 0.4; Hyalella, 30.1; ostracods, 7.9; C\'clops, 2.2; Chydorus sphaericus, 7.9; Pleuroxus pro curs'atus, 0.2; Planorbis, 14.4; Physa, 5.8; oligochaetes, 2.5; fine debris, 5. Summary. — Food: Insect larvae, 21.4; pupae, 1.8; adult inse'cts, 0.4; amphipods, 30.1; ostracods 7.9; copepods, 2.2; cladocerans, 8.1; snails, 20.2; oligochaetes, 2.5; fine debris, 5. Station 3; June 24; number examined, 10. Length: Maximum, 67.5; minimum, 53; average, 57.9 Food: Insect larva, i; Helea larvae, 0.3; Cricotopus trifasciatus larva;, 1.4; Chironomus plumosus larvae 2.1; Tanypus monilis larvx, 3.6; Orthocladius sordidellus larvae, 43; Probezzia glaber larvae, 0.3; P pallida larvae, 1.3; Sialis larva, 0.1; Ecdyurus maculipennis nymphs, 8.3; Orthocladius sordidellus pupae, 0.4; Chironomus digitatus pupae, 0.2; Hyalella, 11. 4; ostracods, 0.3; Cyclops, 0.1; Chydorus, i fine debris, 26. Summury. — Food; Insect larvae, 61.4; pupae, 0.6; amphipods, 11. 4; ostracods, 0.3; copepods, 0.1 cladocerans, i; fine debris, 26. Station 18; July 3; number examined, 11. Length: Maximum, 55; minimum, 41; average, 47.3 Food: Helea larvae, 0.2; chironomid lar\'ae, 3; Chironomus lobiferus larvae, 3.6; C. abbfeviatus lar\'ae 0.2; Probezzia glaber larvae, 0.5; Protenthes culiciformis larvae, 0.3; Procladius sp. larvae, 19.7; Hyalella; 49.1; Dikerogammarus fasciatus, 0.1; Eurycercus, 22.6; algae, +. Summary. — Food: Insect larvae, 27.5; amphipods, 49.2; cladocerans, 22.6; algae, -f . Station 23; August 9; number examined, 3. Lengths: 32.5; 30.5; 25.4. Food: Chironomid larvae, II. 6; Chironomus fulviventris larvae, 3.3; C. viridis larvae, 3.3; C. lobiferus larvae, 6.3: Tanytarsus exiguus larvae, 6.3; Hyalella, 40; ostracods, 5; Cyclops, 1.3; Chydorus sphaericus, 3.3; Ceriodaphnia, 3.3; Eur>-cer- cus, 8.3; oligochaetes, 6.3. Summjiry. — Food: Insect larvae, 30.8; amphipods, 40: ostracods, 5; copepods, 1.3; cladocerans, 14.9; oligochaetes, 6.3. Grand summary for IQI4 and IQIS- — Number examined, 149. Length: Maximum, 67.5; minimum, 25.4; average, 40.4. Food: Fish embr>'os, 0.8; insect eggs, 0.8; insect larvae, 23.4; pupae, 1.7: adult insects, 2.7; mites, 3; amphipods, 14. i; ostracods, 15.7; copepods, 4.9; cladocerans. 15.3: Sphaeridae, 0.4; snails, 3.5; oligochaetes, 2; nematodes, -f ; plant remains, 5.5; algae, 0.9; silt and debris, 4.2. The top minnow ate 36 per cent entomostracans and 28 per cent insects, as well as amphipods, plant remains, the debris from the bottom and the surface of plants, molluscs, etc. Forbes and Richardson (1908 ) reported the food of this species to be insects, amphipods, snails, and plant seeds. The large per- centages of ostracods, oligochaetes, and Chydorida? and the species of insect larva; found in the present investigation indicate that the top miimow frequently feeds near the bottom or among vegetation. Labidesthes sicculus (Cope). Brook silversidc. Data/or Jgi4 (Pearse, 1915). — Number examined, 50. Length: Maximum, 47.9; minimum, 15.4; average, 35.7. Food: Insect larvae, 5.1; pupae and adult insect, 42.4; mites, 0.1; ostracods, +; copepods, 8.1; cladocerans, 27.3; rotifers, -f; protozoans, -f ; plant remains, 2.5; algae, 8; silt and debris, 3.3. Station 23; August 11, 191 5; number examined, i. Length: 25.3. Food: Tanytarsus adults, 40; Cyclops, 15; Chydorus sphaericus, 37; Ceriodaphnia, 8. Station 18; August 14; number examined, 10. Length: Maximum, 27; minimum, 11. 5; average, 20.5. Food: Chironomus eggs, 9.5; chironomid hirvac, 5; Probezzia pallida adult, 11. 5; ostracods, 0.3; Cyclops, 24.7; Chydorus sphaericus, 0.4; Ceriodaphnia, 37.4; Bosmina, 7.3: Pleuroxus procurvatus, 0.1; Camptocercus, 0.2; ephippial eggs, 3.5. Summary. — Food: Insect eggs, 9.5; insect larvae, 5; adult insects, 11.5; ostracods, 0.3; cladocerans, 48.9. FOOD OF THE SHORE FISHES OF CERTAIN WISCONSIN LAKES. 263 Station 19; August 18; number examined, 9. Length: Maximum, 36; minimum, 22; average, 28.2. Food; Chironomid larvae, 2.2; Chironomus viridis pupae, 44.6; C. tentans, pupae, 5.3; Tanytarsus adult, 2.2; Chironomus vnridis adult, 2.7; Cyclops, 5.6; Ceriodaphnia, 37. Summary. — Food: Insect larvae, 2.2; pupae, 49.9; adults, 4.9; copepods, 5.6; cladocerans, 37. Station 18; August 18; Number examined, 5. Length: Maximum, ^^\ minimum, 25; average, 28. Food: Corethra larvae, 0.6; Chironomus viridis adult, 28.8; spider, 0.2; Cyclops, 11; Chydorus, 0.4; Ceriodaphnia, 58; Daphnia hyalina, i. Summary. — Food: Insect larv'je, 0.6; adult insects, 28.8; spider, 0.2; copepods, 11; cladocerans, 59-4. Station 23, west of mouth of Yahara Canal in Lake Monona; August 19; number examined, 5. Length: Maximum, 38.5; minimum, 21.5; average, 31.2. Food: Caterpillar, 1.4; Chironomus viridis pupae, 23; Tanytarsus adult, 3.5; Chironomus viridis adult, ^:}; C. digitatus adult, 2.6; C. tentans adult, 6; spider, 5; Cyclops, 0.6; Chydorus, 4.4; Pleuroxus, +; Daphnia hyalina, 20.4. Summary. — Food: Insect larvae, 1.4; pupae, 23; adults, 45.1; spider, 5; copepods, 0.6; cladocerans, 24.8. Station 24; August 19; number examined, 5. Length: Maximum, 41.5; minimum, 20.5; average, 28. Food: Chironomus viridis lar\'ae, 5; Chironomus viridis pupae, 82.8; Chironomus viridis adults, 5.2;, C. tentans adults, 3.8; spider, 0.2; Cyclops, 2.6; Chydorus, 0.4. Summary. — Food insect larvae, 0.5; pupae, 82.8; adults, 9; spider, 0.2; copepods, 2.6; cladocerans, 0.4. Station 23, at mouth of river; August 19; number examined, 5. Length: Maximum, 41.5; minimum, 21.5; average, 31.5. Food: Corethra larvae, 3; Chironomus viridis pupae, 45; Tanytarsus adult, 5; Chirono- mus viridis adult, 6; C. digitatus adult, 21; spider, i; Cyclops, i; Ceriodaphnia, 7; Eurjxercus, 11. Summary. — Food: Insect larvae, 3; pupae, 45; adults, 32; spider, 1; copepods, i; cladocerans, 18. Station 5; August 25; number examined, 4. Length: Maximum, 80.5; minimum, 30.3; average, 54.4. Food: Cyclops, 15.5; Chydorus, 7; Bosmina, 74.4; Camptocercus, 2.2; rotifers, 0.2; Closterium, 0.2. Summary. — Food: Copepods, 15.5; cladocerans, 83.6; rotifers, 0.2; algae, 0.2. Station 6; August 25; number examined, 6. Length: Maximum, 77; minimum, 25.5; average, 41.6. Food: Chironomus viridis pupae,- 52,5; C. tentans pupae, 14.4; Tanytarsus adult, 2.8; Chironomus viridis adult, 6.6; Cyclops, 3; Ceriodaphnia, 19.6; Bosmina, 1.6. Summary. — Food: Insect pupae, 66.9; adults, 9.4; copepods, 3; cladocerans, 21.2. Grand summary for IQ14 and 191 j. — Number examined, 100. Length: Maximum, 77; minimum, II. 5; average, 40.9. Food: Insect eggs, 1.4; insect larvae, 5.2; insect pupae, 16.4; adult insects, 28.3; spiders, 0.3; mites, +; ostracods, +; copepods, 8.7; cladocerans, 32; rotifers, +; protozoans, +; algae, 4. The silverside is more of a "top-minnow" than the top-minnow (Fundulus diaphamu menona) itself. The fact that its food contains 44.6 per cent adult insects and pupae, 40.7 per cent entomostracans, and only a trace of ostracods can be interpreted in no other way. Forbes and Richardson (1908) stated that this species feeds on animal plankton, chironomid larvae, land insects, and spiders. One fish they examined had eaten a very small minnow. Baker (1916) found the stomachs of the fish he exam- ined to contain a large percentage of insects and small amounts of Crustacea, Acarina and Bryozoa. Lepisosteus osseus (Linnaeus). Long-nosed gar, billfish. Station 28; September 14, 1915; number examined, i. Length: 650. Food: Lepomis incisor, 100. Station 23; September 21; number examined, i. Length:2i8. Food: Lepomis incisor, 98; Simulium vittatum larvae, 2. Station at Oconomowoc Lake; number examined, i. Length: 180. Food: Labidesthes sicculus, go; Chironomus adults, 10. Station 22; July i, 1916; number examined, 5. Length: Maximum, 652; minimum, 480; average, 577. Food: Fish, 40; minnow remains, 40; Enallagma antennatum nymphs, 20. Station 20; July 3; number examined, i. Length: 600. Food: Johnny darter, 100. Station 22; July 8; number examined, i. Length: 416. Food: Fish, 100. Summary for igis and igi6. — Number examined, 10. Length: Maximum, 652; minimum, 180; average, 494.9. Food: Fish, 88.8; insect larvae, 10.2; adult insects, i. The youngest gars examined fed somewhat on insects and larvae, but the chief food of all was small fishes. Forbes and Richardson (1908) reported nothing but small fish for the food of this species. 264 BULLETIN OF THE BUREAU OF FISHERIES. Lepomis incisor Cuvier and Valenciennes. Bluegill, blue sunfish. Da/a /or 797./ (Pearse, 1913). — Number examined, 49. Average length, 30.8. Food: Insect larvae, 22.8; adult insects, 26; mites, 1.2; amphipods, 23.1; copepods, 16.4; cladocerans, 31; oligochaetes, 0.2; nematodes, +; rotifers, +; plants, 1.3; algae, 0.4. Station 13; April 10, 1915; number examined, 7. Length: Maximum, 108; minimum, 53; average, 87.7. Food: Chironomus fulviventris larvae, 9.9; C. decorus larvae, 0.4; Leptocella uwarowii larvae, 0.4; Hcptagenia interpunctata larvae, 0.4; Hyalella, 18.5; Chydorus sphaericus, 0.3 ; plant remains, 27.1; fine debris, 42.1. Summary. — Food: Insect larvae, 11. i; amphipods, 18.5; cladocerans, 0.3; plants, 27.1; fine debris, 42.1. Station 13; April 13; number examined, 14. Length: Maximum, 105; minimum, 46; average, 80.1. Food: Insect eggs, 0.3; chironomid larvae, 0.7; Tanypus monilis larvae, 0.7; Chironomus viridis larvae, 0.7; C. digitatus larvae, 4; C. palliatus larvae, 3.1; C. lobiferus larvae, 0.7; C. fulviventris larvae, 2.1; C. decorus larva, 2.2; Cricotopus trifasciatus larvae, 0.2; Orthocladius sordidellus larvae, i; Pro- cladius larvae, 6.2; Hydroptila larvae, 2.8; Agraylea larvae, 0.3; May-fly nymphs, 2.3; Heptagenia inter- punctata larvae, 2.4; Enallagma hageni nymphs, 14.2; Chironomus lobiferus pupae, 0.7; C. tentans pupae, 0.8; Hyalella, 3.5; ostracods, 0.2; Cyclops, 8; Canthocamptus, 2.7; snail eggs, 5 . 7 ; plant remains, 8.5; algae, 5.3; Aphanothece, 17. i; silt and d^^bris, 2.4. Summary. — Food: Insect larvae, 43.6; pupae, 1.5; amphipods, 3.5; ostracods, 0.2; copepods, 10.7; snail eggs, 5.7; plants, 8.5; algae, 22.4; silt and d(5bris, 2.4. Station 21, on south shore of Lake Wingra; April 28; number examined, i. Length: 27.5. Food: Chironomus lobiferus larvae, 5; C>-clops, 84; Chydorus sphaericus, 11. Station 5; May 12; number examined, 5. Length: Maximum, 58; minimum, 32; average, 47.1. Food: Insect larvae, i; chironomid larvae, 15; Chironomus lobifererus larva, 1.2; C. decorus larvae, + ; C. fulviventris larvae, 4; Pelopia monilis larvae, o.i; Cricotopus trifasciatus lar\'ae, 5.9; Corethra lar\'ae, 6.4; May-fly nymphs, 17; Siphlurus nymphs, 7; chironomid pupae, 2.4: Cricotopus trifasciatus adults, 5; adult midges, 5; mites, 1.8; Arrhenurus, 2; Hyalella, 24.2; ostracods, 0.7; Eurycercus, 0.8; Chydorus sphaericus, 0.5; algae, 0.1. Summary. — Food: Insect larvae, 56.6; pupae, 2.4; adult insects, 10; mites, 3.8; amphipods, 24.2; ostracods, 0.7; cladocerans, 1.3; algae, o.i. Station i5; May 15; number examined, 7. Length: Maximum, 56; minimum, 41; average, 48.8. Food: Insect larvae, 0.7; Cricotopus trifasciatus larvae, 77.4; Orthocladius sordidellus larvae, 7; I'ro- bezzia pallida larvae, 0.9; P. glaber larvae, 0.7; chironomid pupae, 7; Hyalella, 5.6; ostracods, 0.4; Planorbis, 0.1; algae, 0.1. Summary. — Food: Insect larvae, 86.7; pupae, 7; amphipods, 5.6; ostracods, 0.4; Planorbis, 0.1; algae, 0.1. Station 3; June 4; number examined, 2. Lengths: 115, 117. Food: Helea larvae, 1.5; chironomid larvae, i; Chironomus lobiferus larvae, i; Simuliura vittatum larvae, 10; PeItod>-tes edentulus lar\'ae, 2.5; Tabanuspupae, 5; Hyalella, 3.5; ostracods, 0.4; Eurycercus, 52.5; Physa, 0.5; leech, 17.5; plants, 5. Summary. — Food: Insect larvae, 16; pupae, 5; amphipods, 3.5; cladocerans, 52.5; snails, 0.5; leech, 17.5; plants, 5. Station 23; June 14; number examined, 2. Lengths: 44, 42. Food: Chironomus tentans larvae, 5; Orthocladius sordidellus lars'ae, 5; Chironomus lobiferus pupae, 5; Orthocladius sordidellus pupae, 7.5; chironomid pupae, 4; Hyalella, 73.5. Summary. — Food: Insect larvae, 10; pupae, 16.5; amphipods, 73.5. Station 2; June 15; number examined, 7. Length: Maximum, 58; minimum, 43.5; average, 50.1. Food: Helea larvae, 0.4: chironomid larvae, 3.5; Chironomus fulviventris lar\'ae, 4.4; Ortliocladius sor- didellus larvae, 4.5; Orthocladius sp. larvae, 1.2; Protenthcs monilis larvae, 1.4; Probezzia pallida larvae, 2.5; caddis-fly larva and case, 1.4; Caenis diminuta nymphs, 13; Callibaetis nymphs, 11; Enallagma hageni nymphs, 9; E. antennatum nymphs, i; Chironomus lobiferus pupae, 17; mites, i; Hyalella, 16; ostracods, 2; Cj'clops, 2; Eurycercus, i; Chydorus, 0.1; ephippial eggs, 0.1; Planorbis, 6.8. Summary. — Food: Insect larvae, 53.3; pupae, 17; mites, i; amphipods, 16; ostracods, 2; copepods, 2; cladocerans, 1.2; snails, 6.8. Station 27; June 17; number examined, 8. Length: Maximum, 124; minimum, 69; average, 100.9. Food: Chironomus lobiferus larvae, 13. i; Palpomyia longipennis larvx, 8; Orthocladius sor- didellus larvae, 12; Probezzia pallida larvae, 10.2; caddis-fly larvae in cases, 7.2; Chironomus lobiferus FOOD OF THE SHORE FISHES OF CERTAIN WISCONSIN LAKES. 265 pupae, 15; Orthocladius sordidellus pupae, 9.8; Palpomyia longipennis pups, i; Probezzia jjallida pupae, 0.2; adult midges, +; Corixa adults, 11. 4; Camponotus adult, o.i; mites, 0.2; Lebertia, 2; Hyalella, 8.1; ostracods, o.i; Eurj'cercus, 2.5. Summary. — Food: Insect larvae, 50.5; pupae, 26; adult insects, 11. 5; mites, 2.2; amphipods, 8.1; ostracods, 0.1; cladocerans, 2.5. Station 28; June 17; number examined, 10. Length: Maximum, S3; minimum, 39.5; average, 58.9. Food: Insect larvae, 0.5; Chironomus tentans larvae, 5.8; C. lobiferus larvae, 1.4; Orthocladius sordidellus larvs, 26; Probezzia pallida larvje, 1.5; Corethra larvae, 0.5; May-fly nymphs, 3.6; Ecdyu- rus maculipennis nymphs, 11.5; Caenis diminuta nymphs, 3.5; Enallagma antennatum nymphs, 2; chironomid pupae, 5; Chironomus lobiferus pupae, i.i; C. tentans pupae, 0.2; Orthocladius sordidellus pupae, 20.9; Corixa adults, 10.7; mites, 0.2; Cyclops, 0.5; Eurycercuslamellatus, 4.8; Camptocercus, 0.1. Summary. — Food: Insect larvae, 55.7; pupae, 27.2; adult insects, 10.7; mites, 0.2; copepods, 0.5; cladocerans, 4.9. Station 3; June 24; number examined, 10. Length: Maximum, 68.5; minimum, 44; average, 54.8. Food: Tanypus monilis, 1.6; Chironomus tentans larvae, 6.3; C. digitatus larvae, 0.4; C. lobiferus larvae, 14; Palpomyia longipennis larvae, 4.5; Orthocladius sordidellus larvae, 25.8; Probezzia pallida larvae, 13.8; Leptocella larva and case, 2.8; May-fly nymphs, 2.3; EcdyiuTis nymphs, 6.2; Peltodytes eden- tulus larvae, 0.3; Chironomid pupae, 1.5; Chironomus digitatus pupse, 0.5; Orthocladius sordidellus pupae, 3.4; Probezzia pallida pupae, 0.7; sawfly adult, 0.2; Chironomus lobiferus adults, 7.7; mites, 0.1; Hyalella, 0.9; ostracods, 0.1; Eurycercus, 0.3; Planorbis, 5.2; Physa, 0.3. Summary. — Food: Insect larvae, 78; pupae, 6.1; adult insects, 7.9; amphipods, 0.9; ostracods, 0.1; cladocerans, 0.3; snails, 5.5. Station 18; July 3; number examined, 10. Length: Maximum, 65; minimum, 33.8; average, 45.4. Food: Tanypus monilis larvae, 0.3; Chironomus viridis larvae, 0.3; C, digitatus larvae, 4.4; C. palliatus larvae, 6.3; Cricotopus trifasciatus larvae, 0.2; Orthocladius sordidellus larvae, 3.4; Procladius larvae, 12; May-fly nymphs, 0.2; Peltodytes edentulus larvae, 0.2; C. lobiferus pupae, 2.7; C. tentans pupae, 1.2; mites, 3.2; Hyalella, 9.8; cladocerans, 8.4; Eurycercus, 47.1. Summary. — Food: Insect larvae, 27.3; pupae, 3.9; mites, 3.2; amphipods, 9.8; cladocerans, 55.5. Station 23; July 9; number examined, 5. Length: Maximum, 80; minimum, 54; average, 65.7. Food: Insect larvae, 15; Chironomus tentans larvae, 4.2; C. fulviventris larvae, 3.4; Leptocella uwarowii larvae, 3.6; May-fly nymphs, 0.4; chironomid pupa, 12; Chironomus viridis pupje, 0.6; Corixa adults, 2; leaf-hopper, 2; mites, 0.2; Hyalella, 19.4; Physa, 28.2; leech, 11. Summary. — Food: Insect larvae, 26.6; pupae, 12.6; adult insects, 4; mites, 0.2; amphipods, 19.4; snails, 28.2; leech, 11. Station 13; July 23; number examined, 2. Lengths; 60, 37. Food: Insect larvae, i; Probezzia glaber larvae, 25; chironomid larvae, i; C. tentans larvae, 3; C. lobiferus larvae, 12; Probezzia glaber pupae, 2.5; Hyalella, 44; Chydorus sphaericus, 1.5; Physa, 32.5. Summary. — Food: Insect larvae, 19.5; pupae, 2.5; amphipods, 44; cladocerans, 1.5; snails, 32.5. Station 23; July 23; number examined, 3. Lengths: 73,71,65. Food: Chironomus viridis larvae, 11.3; C. vulviventris larvae, 37.6; C. tentans larvae, 8.3; Pelopia monilis larvae, 6; Probezzia glaber larvs, 0.6; Hydroptila larvae, 0.3; Simulium vittatum larvae, 1.6; Peltodytes edentulus larvae, 0.6; Chironomus viridis pupae, 4.3; Arrhenurus, 0.1; Hyallela, 5; Ancylus, 0.3; Planorbis, 0.3; Physa, 21.6; snail eggs, 0.6. Summary. — Food: Insect larvae, 66.3; pups, 4.3; mites, 0.1; amphipods, 5; snails, 22.8. Station 7, in swamp along shore; August 25; number examined, 4. Lengths: 30, 27.5, 17.8, 15. Food: Tanypus monilis larvae, 3.7; Ceenis diminuta nymphs, 1.2; Corixa adult, 1.2; Cyclops, 30.1; Cantho- camptus, 2.5; Bosmina longirostria comuta, 28.4; Camptocercus, 5; Eurycercus, 20; algae, 9. Summary. — Food: Insect larvae, 4.9; adult insects, 1.2; copepods, 30.1; cladocerans, 53.4; algae, 9. Grand summary for jgi4and igis- — Number examined, 149. Length; Maximum, 115; minimum, 15; average, 51. i. Food: Insect larvae, 38; pupae, 6; adult insects, 2.2; mites, 0.7; aquatic isopods, +; amphipods, 14.4; ostracods, 0.4; copepods, 7.9; cladocerans, 16.6; gastropods, 4.5; oligochaetes, 0.1; leeches, 0.6; nematodes, +; rotifers, -f; plants, 2.9; algae, 2.3; silt and debris, 2.2. The bluegill feeds mostly on insects (46.2 per cent) and entomostracans (24.9 per cent). Its shape and its food indicate that it feeds much among water plants. Forbes and Richardson (1908) found the food to consist of a trace of fishes, some snails, 45 per cent insects, and many medium-sized crustaceans. They state that this species eats more large insect larvae than any other sunfish. Hankinson (1908), 266 BULLETIN OF THE BUREAU OF FISHERIES. found insect larvae, midges, and cra>'fish; after the middle of May, crayfishes, grasshoppers, crickets, beetles, and entomostracans. Reighard (1915) found the bluegill only in shallow water among vegeta- tion. Its food was plants, bryozoans, insects, mites, and ostracods. Micropterus dolomieu Lac^p^de. Smallmouth black bass. Data for IQ14 (Pearse, 1915). — Stations 19 and 24; number examined, 2. Lengths; 78, 59. Food: Dipterous larvx, 10; adult Diptera, 5; Corixa, 85. Station 28; August 19, 1915; number examined, I. Length: i8i. Food: Minnow, 40; Chironomus lobiferus larvae, 5; Corixa adults, 15; plant remains, 5; algse, 10; silt and debris, 25. Station 24; August 19; number examined, 3. Lengths: 175, 148, 132. Food: Fish remains, 29.9; Lepomis incisor, 30; May-fly nymphs, 5; Corixa adults, 32.6; plant remains, 1.3; filamentous algae, i. Station 12; August 20; number examined, 8. Length: Maximum, 48.5; minimum, 29; average, 36. Food: Chironomus digitatus larvae, 20; Baetisca nymphs, 22.5; Caenis diminuta nymphs, 0.3; EcdyuniS' raaculipennis nymphs, 9; Chironomus lobiferus pupae, 2: C. digitatus pupae, 7; C. flavescens adults, 5.6; Limncphilus adult, 2; Corethra adult, 17; Daphnia longispina hyalina, 4; Eurycercus lamellatus, 0.2; Ceriodaphnia, 1.8; Bosmina, -f-; oligochaetes, 8.6. Summary. — Food: Insect larvae, 51.8; pupae, 9; adult insects, 25.2; cladocerans, 6; oligochaetes, 8.6. Station 14; August 31; number examined, I. Length: 33.5. Food: Protenthes culiciformis larvae. 40; Chironomus viridis pupae, 18; C. lobiferus pupae, 19; Tanjiarsus monilis pupae, 18; Eiuycercus, 5. S^tmmary. — Food: Insect larvae, 40; pupae, 55; cladocerans, 5. Grand summary/or iQJ4and ipiy — Number examined, 15. Length: Maximum, 181; minimum, 29; average, 72.5. Food: Fish, 14.7; insect larvae, 33.1; pupae, 7.6; adult insects, 32.1; cladocerans, 3.4; oligochaetes, 4.6; plants, 0.6; algae, 0.8; silt and debris, 1.5. The food of the young smallmouth black bass apparently consists largely of insects and their larvae. Adults eat fish, crayfish, frogs, and plants as well. Forbes and Richardson (1908) examined only three specimens and found one-third fishes and two-thirds craj-fishes. Tracy (igio) reports small fish, insects and their larvae, and crustaceans. Reighard (1915) examined eight and found crayfish, afrog, and fishes. Micropterus salmoides Lac^pfede. Largemouth black bass. Data for IQ14 (Pearse, 1915). — Number examined, 25. Length: 64.4. Food: Fish, 17.8; insect larva;, 31.6; adult insects, 40.6; Hyalella, 3.8; copepods, +; cladocerans, 2.5; plants, 1.6. Station 71; April 17, 1915; number examined, I. Length: 225. Food: Fish 95; leech, 5. Station 17; April 25; number examined, i. Length: 470. Food: Ostracods, o.i; diatoms, 0.4; Aphanothece, 20; filamentous algae, 24.5; plant remains, 50; debris, 5. Summary. — Food; Ostracods, o.i; algs, 44.9; plant remains, 50; debris, 5. Station 3; June 24; number examined, i. Length; 81. Food; Ecdyurus maculipennis nymphs, lo; Knallagma antennatum nymphs, 20; dipterous adult, 5; Corixa adult, 30; craj^sh, 20; Hyalella, 15. Station 23; July 9; number examined, 3. Lengths: 32, 30.3, 29.5. Food: Chironomid larvae, 10; Chironomus fulviventris larvae, 6.3; C. tenellus larvae, 17; C. tentans larvae, 0.6; May-fly nymphs, i; Dytiscushybridus larvae, 5; Chironomus tenellus pupae, 16; adult midges, 6.6; Simulium \'itattum adults, 8.3; Cyclops, 20; Chydorus sphaericus, 2; ephippial eggs, 0.2; oligochaetes, 6.6; Oscillairia, 0.3. Summary. —Food: Insect larvae, 39.9; pupae, 16; adult insects, 8.3; copepods, 20; cladocerans. 2.2; oligochaetes, 6.6; algae, 0.3. Station 23; July 12; number examined, i. Length: ^;}. Food: Chironomus fulviventris larvae, 3S; Anax Junius nymphs, 8; C. fulviventris pupae, 20; Corixa adult, 7; oligochaetes, 30. Station s; August9;numberexamined, I. Length;4i.6. Food: May-fly nymphs, 65; Hyalella, 35. Station 17; August 23; number examined, I. Length: 147. Food: Adult dragon fly, 100. Station 23, in pool in Tenney Park; August 11; number examined, I. Length: 62. Food: Cyclops, 65; Simoccphalus, 10; Eurycercus lamellatus, 25. Station 3; August 18; number examined, 12. Length: Maximum, 62; minimum, 38.3; average, 50.8. Food: Chironomus fulviventris larvae, 0.3; Baetisca nymphs, 23.2; Caenis diminuta nymphs, 3.6; Corixa nymphs, i.t; C. lobiferus pupae, 0.8; Corixa adults, 30; Micronecta adult, 0.4; Hyalella, 25; ostracods, 0.3; Eurycercus lamellatus, 12.4; ephippial eggs, 1.2; seeds, 0.2. Summary. — Food: Insect larvae, 29.4; pupae, 0.8; adult insects, 30.4; Hyalella, 25; ostracods, 0.3; cladocerans, 13.6; plants, 0.2. FOOD OF THE SHORE FISHES OF CERTAIN WISCONSIN LAKES. 267 Station 5; August 18; number examined, 3. Lengths: 68.5, 58, 49.5. Food: May-fly nymphs, 20; Corixa adults, 55; Hyalella, 25. Station 18; August 18; number examined, 15. Length: Maximum, 64; minimum, 36; average, 46.4. Food: Fish remains, 5.3; chironomid larvae, 0.6; Chironomusviridis larvae, i; Protenthes chorcus larvae, 1.3; Corethra larvae, 1.3; May-fly nymphs, 0.6; Baetisca nymphs, 4.3; Naucoris nymphs, 2.4; Corixa nymph, 0.6; Chironomus viridis pupae, 3; adult midges, 2.;^; adult Diptera, 2: Chironomus viridis adults, 2.3; adult Corixas, 0.6; Halictus adults, 0.6; Platyphylax subfasciatus adults, 4; Hyalella, 17; ostracods, 0.3; Diaptomus, 0.4; Cyclops, 7.5; Ceriodaphnia, 21.6; Eurycercus, 0.4; Daphnia longispina hyalina, 18.6; Bosmina, -|-; Pleuroxus, -|-; Camptocercus, 0.3; Scapholeberis, -|-; Aphanothece, 0.3. Siimmary. — Food: Fish remains, 5.3; insect larvae, 12. i; pupae, 3; adult insects, 7.4; amphipods, 17; ostracods, 13; cladocerans, 40.9; algae, 0.3. Station 8; August 20; number examined, 5. Length: Maximum, 64: minimum, 47; average, 52.6; Food: Probezzia glaber larvae, 0.2; Baetisca nymphs, 12; Ecdyurus maculipennis nymphs, 0.8; Enallagma antennatum nymphs, i ; Naucoris nymph , i ; Corixa adults, 30.8 ; Agraylea multipunctata adult, i ; Lep- tid adult, 7; Tabanid fly, 3; Hyalella, 29.8; Ceriodaphnia, 8.6; Eurycercus, 4.4; Aplexa hypnorum, 0.4. Summary. — Food: Insect larvae, 14; adult insects, 41.8; amphipods, 29.8; cladocerans, 13; snail, 0.4. Station 14; August 31; number examined, 3. Lengths: 44, 42.6, 42. Food: Baetisca nymphs, 15; Caenis diminuta nymphs, ^-i'' Chironomus adults, 6.6; Agraylea multipunctata adults, 13.3; Hyalella, 26.3; Chydorus sphaericus, 1.6; Ceriodaphnia, t,^; chydorid, 0.3; Camptocercus, 0.3. Summary. — Food: Insect larvae, 1S.3; adult insects, 19.9; amphipods, 26.3; cladocerans, 35.2. Station i; September i; number examined, 2. Lengths: 46, 38. Food: Baetisca nymphs, 16.5; chironomid pupae, 1.5; Chironomus viridis pupae, 6; C. v. adults, 6.5; Hyalella, 1.5; ostracods, 0.5; Chy- dorus, i; Simocephalus, 41.5; Eurycercus, 25. Summary. — Food: Insect larvae, 16.5; pupae, 2.1; adult insects, 6.5; amphipods, 1.5; ostracods, 0.5; cladocerans, 67.5. Station 29; November 16; number examined, 3. Lengths: 338, 327, 270. Food: Frog, 6.6; fish, 33.3; crayfish, 60. Grand summary for igi4 and IQI§. — Number examined, 78. Length: Maximum, 470; minimum, 29.5; average, 66.8. Food: Frogs, 0.2; fish, 8.7; insect larvae, 23; pupae, 3.1; adult insects, 28.1; cray- fishes, 2.6; amphipods, 13.9; ostracods, o.i; copepods, 2.9; cladocerans, 15.1; snails, +; oligochaetes, 0.7; leech, -f ; plant remains, 1.2; algae, 0.7; fine debris, o.i. The largemouth black bass feeds more on insects and their larvae (34.2 per cent) than anything else, though amphipods (13. 9 per cent), entomostracans (18. i per cent), and fish (8.7 per cent) are also taken in considerable quantities. Young individuals eat more small insects and entomostracans than adults. The largest bass examined ate nothing but fish, crayfish, and frogs. Forbes and Richardson (1908) found the food of this species to consist of fish and crayfishes. Hankinson (1908) stated that crayfishes and insect larvae are the most important foods. Tracy (1910) mentioned small fish, crayfishes, frogs, insects, and all other aquatic animals of suitable size. Reighard (1915) found perch and crayfish in those he examined. Notropis heterodon (Cope). Shiner, minnow. Data for 1914 are not reliable and therefore not included in this paper. Station 17; April 6, 1915; number examined, 10. Lengths: Maximum, 49.6; minimum, 18.7; aver- age, 34.4. Food: Pelopia larvae, 2.5: Chironomus larvae, 13; adult midges, 13; ostracods, i; Cyclops and nauplii, 19.5; Camptocamptus, 4.5; Chydorus, 6.5; cyst, 0.5; rotifers, 9.3; plant remains, 2; filamentous algae, 10; Pleurococcus, 5.9; desmids and diatoms, 0.1; fine debris, 11. 2. Summary. — Food: Insect larvae, 16; adult insects, 13; ostracods, i; copepods, 24; cladocerans, 6.5; rotifers, 9.3; plants, 2; algae, 16; fine debris, 11. 2. Station 17; April 7; number examined, 7. Length: Maximum, 50; minimum, 24.5; average, 34.7. Food: Chironomus larvae, 1.4; adult midges, 2; mites, 10; ostracods, 3; Cyclops, 33; Canthocamptus, 8; Chydorus, 4; cladocerans, 1.4; ephippial eggs, 4.7; rotifers, 12; Pandorina, 0.6; plant remains, 7; Wolffia, 10; filamentous algae, 3.1; desmids and diatoms, 0.1; fine debris, 8.2. Summary. — Food: Insect larvae, 1.4; adult insects, 2; mites, 1.4; ostracods, 3; copepods, 41; cladoc- erans, lo.i; rotifers, 12; plants, 17; algae, 3.8; debris, 8.2. 268 BULLETIN OF THE BUREAU OF FISHERIES. Station 5; May 12; number examined, 8. Length: Maximum, 47.5; minimum, 28.6; average, 36.3. Fcx)d: Chironomus larvae, 2.5; Camptocercus, o.i; Chydorus, 27.8; cladocerans, 1.2; plant remains, i; filamentous algse, 49.5; fine debris, 17.7. Summary. — Food: Insect larvje, 2.5; cladocerans, 29.1; plants, i; algae, 49.5; debris, 17.7. Station 16; May 15; number examined, 6. Length: Maximum, 54; minimum, 26; average, 31.9. Food: Insect eggs, 8; Orthocladiussordidellus larvae, 6.6; Chironomus larvae, i4.i;ostracods, 0.5; Cyclops, II. 6; Canthocamptus, 20.5; Pleuroxus, +; Chydorus, o.i; oligochaetes, 29.1; Oscillaria, 3.3; desmids and diatoms, 4.5. Summary. — Food: Insect larvae, 28.7; ostracods, 0.5; copepods, 32.1; cladocerans, 0.1; oligochaetes, 29.1; algae, 7.8. Station 5; June i; nixmber examined, i. Length: 47.5. Food: Chironomus larvae, 85; Cyclops, 9; chydorids, 6. Station 5; June 24; number examined, 9. Length: Maximum, 42.6; minimum, 32.2; average, 36.2. Food: Orthocladius sordidellus lar\'ae, 2.5; Tanytarsus dives larvae, 2.5; Chironomus lar\'ae, 0.1; C. tentans larvae, 10; Heptageniainterpunctata larvae, 6.1; Orthocladius sordidellus pupae, 21.5; Chirono- mus pupae, II. i; Tanytarsus dives adults, 1.6; Hydroptilus undulatus adults, 4.3; Stenelmis crenatus adult, 2.6; ephippial eggs, 2.2; Wolffia, 14; sand, 21.5. Summary. — Food: Insect larvae, 21.2; pupae, 32.6; adult insects, 8.5; cladocerans, 2.2; plants, 14; sand, 21.5. Station 19; July 3; number examined, 11. Length: Maximum, 45; minimum, 35; average, 39.9. Food: Chironomus lobiferus larvae, 3.4; Cricotopus trifasciatus larvae, 4.5; adult insects, 1.3; mites, i; Eurycercus, 5; Bosmina, i; Ceriodaphnia, 0.5; Daphnia longispina hyalina, 42.6; Daphnia, 5.4; Pleu- roxus, 0.1; Chydorus, 13.5; chydorids, 1.4; Wolffia, 3.2; filamentous algae, 16.8. Summary. — Food: Insect larvae, 7.9; adult insects, 1.3; mites, i; cladocerans, 69.5; plants, 3.2; algae, 16.8. Station 18; August 18; number examined, 8. Length: Maximum, 49; minimum, 24; average, 35.7. Food: Chironomus larvae, 0.6; Corethra adults, 6.3; Triaenodesflavesccns adults, 5.6; sapromyzid fly, 2; Ceriodaphnia, 25.5; Daphnia longispina hyalina, 58.8; Chydorus sphaericus, 1.2. Summary. — Food: Insect larvae, 0.6; adult insects, 13.9; cladocerans, 85.5. Station 18; August 21; number examined, 10. Length: Maximum, 30.5; minimum, 16.8; average, 24.5. Food: Chironomus larvae, i; Corethra adults, 7; Chironomus tantans adults, 6; C. viridis adults, 25; Probezzia glaber adults, 6.2; chalcid fly, 4.3; Hyalella, 0.8; Cyclops, 8.5; Camptocercus, i; Bos- mina, 5.5; Ceriodaphnia, 27; Daphnia longispina hyalina, 3; ephippial eggs, 3.5; Hydrodictyon, 1.2. Summary. — Food; Insect larvae, i; adult insects, 48.5; amphipods, 0.8; copepods, 8.5; cladocerans, 39; algae, 1.2. Station 17; August 23; number examined, 10. Length: Maximum, ^i'. minimum, 19.8; average, 24.5. Food: Probezzia larvae, 2.5; Chironomus lobiferus lars'ae, 33. 3; pamid larvae, 0.3; hemipterous nymph, i; Chironomus pupae, 2; Tanytarsus dives adults, i; mites, 2.4; ostracods, 0.5; Cyclops, 7.8; Canthocamptus, 0.5; Acroperus, 0.2; Camptocercus, 0.4; Bosmina, 0.5; Simocephalus, 41.2; Chydorus, 3.9; oligochaetes, 2. Summary. — Food: Insect larvae, 36.1; pupae, 1.2; adult insects, i; mites, 2.4; ostracods, 0.5; cope- pods, 8.3; cladocerans, 46.2; oligochaetes, 2. Grand summary. — Number examined, 80. Length: Maximum, 54; minimum, 16.8; average, 34. Food; Insect eggs, 0.7; insect larvae, 12.8; pupae, 4; adult insects, 9.2; mites, 0.5; amphipods, 0.1; ostra- cods, 0.5; copepods, 11; cladocerans, 33.4; oligochaetes, 2.1; rotifers, 2.2; plants, 3.9; algae, 11. 7; debris, 4.1; sand, 2.4. The food of this miimow consists for the most part of entomostracans (44.9 per cent), aquatic plants and algae (15.6 per cent), and insects (26.7 per cent). The sparcity of ostracods and oligochaetes indi- cates that it does not feed on the bottom . The abundance of Canthocamptus, chydordis, algse, and rotifers make it probable that the food is secured among aquatic vegetation. Forbes and Richardson (1908) found the food to be mostly entomostracans, also insect larvae, amphipods, flowers, seeds, and algae. Hankinson (1908) reported adult midges, algae, and a few entomostracans. FOOD OF THE SHORE FISHES OF CERTAIN WISCONSIN LAKES. 269 Perca flavescens (Mitchill). Yellow perch, ring perch, American perch. Data/or I()I4 {PeaTse, igi$). — Number examined, 16. Average length : 92.5. Food; Insect larvae, 19.5; adult insects, 2.7; mites, 0.5; Hyalella, 32.8; ostracods, 0.3; copepods, 0.2; cladocerans, 36.6. Station 6; June 24, 1915; number examined, 10. Length: Maximum, 127; minimum, 76; average, 111. 4. Food: Fish eggs, 3; Chironomus plumosus larvae, 0.3; C. lobiferus larvae, 2.5; Orthocladius larvae, 8; Cricotopus trifasciatus larvae, 1.5; Probezzia larva, 1.2; Enallagma antennatum nymphs, 0.5; Caenis diminuta larvae, 4.1; Heliopsyche borealis larvae, 5.1; Leptocella uwarowii larvae, 11; Agraylea larvse, o.i; Cricotopus trifasciatus pupae, 0.4; Chironomus pupae, 0.2; C. lobiferus pupae, i; mites, 0.2; Hyalella, 40.6; Planorbis, 0.8; Sphaeridae, 0.8; oligochaetes, 3; seeds, o.i; plant remains, 2.5; fine debris, 7. Summary. — Food: Insect larvae, 43.3; pupae, 1.6; mites, 0.2; amphipods, 40.6; snails, 0.8; clams, 0.8; oligochaetes, 3; plants, 2.6; debris, 7. Station 5; August 18; number examined, 2. Lengths: 135, 113. 5. Food: Caenis diminuta larvae, 10; Baetisca larvae, 5; Chironomus adult, 2.5; Corixa adults, 51.5; Hyalella, 30.7; Arcella, 0.1; filamentous algae, 0.3. Summary. — Food: Insect larvae, 15; adult insects, 54; amphipods, 30.7; protozoans, 0.1; filamentous algae, 0.3. Station 15; August 21; number examined, 2. Lengths: 138, 132. Food: Daphnia longispina hya- lina, 100. Station 17; August 23; number examined, 10. Length: Maximum, 187; minimum, 123; average, 156.5. Food: Tadpoles, 3.5; Chironomus digitatus larvae, i.i; C. tentans larvae, 2.5; C. modestus larvae, i; Palpomyia longipennis larvae, 0.2; Aeschna umbrosa nymphs, 12; Enallagma hageni nymphs, 9.6; Celithemis eponina nymphs, 1.8; Caenis diminuta nymphs, 3.4; Baetisca nymphs, 25.6; neuropteron larvae, 2.2; Chironomus digitatus pupae, 2.4; Gryllus nymphs, 0.1; Corixa adults, 4; Dytiscid beetle, 0.3; Naucoris adult, 0.1; Scirtes adult, 0.2; Hyalella, 8.3; ostracods, 0.1; Cyclops, +; Eurycercus, 0.1; Planorbis, 2.2; Physa, 17. i; Arcella, 0.1; fine debris, i. Summary. — Food: Insect larvae, 63.9; pupje, 2.6; adult insects, 4.6; amphipods, 8.3; ostracods, 0.1; cladocerans, 0.1; snails, 19.3; protozoans, 0.1; debris, i. Station 18; August 18; number examined, 3. Lengths of each : 100. Food: Chironomus lobiferus larvae, i.i; C. digitatus larvae, 1.2; Probezzia larvae, 0.3; Baetisca nymphs, 1.3; Chironomus digitatus pupae, 2; Triaenodes flavescens adults, 1; mites, 1.6; Hyalella, 90.8; Cyclops, 0.1; filamentous algae, 0.3. Summary. — Food: Insect larvae, 3.9; pupae, 2; adult insects, i; mites, 1.6; amphipods, 90.8; cope- pods, 0.1; algae, 0.3. Station 18; September 22; number examined, 2. Lengths: 146, 180. Food: Fish, 80; Hyalella, 17.5; Myriophyllum, 5. Station 15; October 2; number examined, I. Length: 124. Food: Daphnia longispina hyalina, 9S; D. pulex, 5. Station 29; October 11; number examined, 2. Lengths: 63.5,63.5. Food: Chironomus lobiferus larvae, 15.5; C. decorus larvae, 25; Enallagma antennatum n^'mph, 40; ostracods, i; Cyclops, 2.5; Daphnia pulex, 7.5; oligochaetes, 7.5; diatoms, i. Summary. — Food: Insect larvae, 80.5; ostracods, i; copepods, 2.5; cladocerans, 7.5; oligochastes, 7.5; alga, I. Station 26; December 4; number examined, 8. Length: Maximum, 280; minimum, 245; average, 265. Food: Fish, 10; Chironomus decorus larvae, 84; Sialis larvae, 5.6. Station 28; May 30, 1916; number examined, 5. Length: Maximum, 229; minimum, 160; average, 186. Food: Fish eggs, 0.2; Chironomus lobiferus larva:, 5.4; C. sp. larvae, 3.2; Enallagmahageni nymphs, 16.4; Atax turgidus nymphs, i; Corixa sp. nymphs, 17.6; Chironomus sp. pupae, 7; Hyalella, 15.6; ostra- cods, 0.2; Physa, 4; filamentous algae, 11.6; plant remains, 3; mud, 7.6; debris, 3. Summary. — Food: Fish eggs, 0.2; insect larvae, 43.6; insect pupae, 7; amphipods, 15.6; ostracods, 0.2; MoUusca, 4; algae, 11. 6; plants, 3; debris, 10.6. Station in Oconomowoc Lake; June 14; number examined, 13. Length: Maximum, 67; minimum, 54; average, 57.8. Food: Chironomus sp. larvae, 8.4; Probezzia glaber larvae, 3.4; Procladius sp. larvae, 0.3; Enallagma antennatum nymphs, 7; Chironomus sp. pupae, 4.7; Hyalella, 18.7; ostracods, 0.3; Cyclops, 32.7; Daphnia, 18.8; Chydorus sphasricus, 2.3; Eurycercus, 0.5; Physa, 0.6; filamentous algae, 1.4. Summary. — Food: Insect larvae, 19. i; insect pupae, 4.7; amphipods, 18.7; entomostracans, 54.6; Mollusca, 0.6; algae, 1.4. 270 BULLETIN OF THE BUREAU OF FISHERIES. Station i6; June 30; number examined, 10. Length: Maximum, 173; minimum, 139; average, 149.6. Food: Chironomus sp. larvae, 7; Pelocaris femoratus larvae, 2; Stratiomyia sp. larvae, i; Enal- lagma antennatum nymphs, 4.1; Enallagma hageni nymphs, 5.5; Atax turgidus nymphs, 1.5; Corixa sp. nymphs, 30.6; Limnesia, 0.7; Hyalella, 5; Cyclops, 0.2; Eurycercus, 17; Physa, 5; snails, 16.2; plant remains, 4.9; debris, 0.5. Summary. — Food: Insect larvae, 51.7; mite, 0.7; amphipods, 5.; entomostracans, 17.2; MoUusca, 21.2; plants, 4.9; debris, 0.5. Station 17; July 7; number examined, 10. Length: Maximum, 3:j; minimum, 25; average, 29.6. Food: Chironomus fulviventris larvae, 1.6; Tanypus decoloratus larvae, 6.9; Plea minutissima larvae, o.i; Corixa sp. nymphs, 1.5; Chironomid adult, o.i; Hyalella, 15.3; ostracods, 0.1; Cyclops viridis, 2.9; Cyclops, 40.4; Nauplii, 2.7; Daphnia, 0.1; Chydorus sphaericus, 8.9; Eiuycercus, 11. 8; Acroperus, 0.2; Ceriodaphnia, 0.1; Pleuroxus prociu-vatus, 0.5; Bosmina, 6.5. Summary. — Food: Insect larvae, lo.i; adult insects, 0.1; amphipods, 15.3; Entomostraca, 74.2. Station 17; July 19; number examined, 9. Length: Maximum, 38.5; minimum, 34; average, 36.8. Food: Chironomus fulviventris larvae, 9.1; Chironomus sp. larvae, i.i, Procladius sp. larvae, 0.9; Cri- cotopus trifasciatus larvae, 3.7; May-fly nymphs, 5.5; Hyalella, 55.4; ostracods, 2.5; Cyclops, 0.2; Chy- dorus spliaericus, 0.7; Eurj-cercus, 17.2; Ceriodaphnia, 4.6; Pleuroxus procur\atus, 0.3. Summary. — Food: Insect lar\'ae, 20.3; amphipods, 55.4; Entomostraca, 25.5. Station 18; August 7; number examined, 10. Length: Maximum, 54.5; minimum, 45.6; average, 50.4. Food: Chironomus fuh-iventris larvae, 16.2; May-fly nymphs, 24.9; Enallagma anteimatum nymphs, 4.5; Corixa sp. adult, 0.3; Hyalella, 39.6; ostracods, 0.8; Cyclops, 0.4; Daphnia, 0.5; Cerio- daphnia, 13.9; filamentous algae, 0.9: plant remains, 0.2. Summary. — Food: Insect larvae, 45.6; adult insects, 0.3; amphipods, 39.6; Entomostraca, 15.6; algae, 0.9; plants, 0.2. Station 18; September 13; number examined, 2. Length: Maximum, 185; minimum, 182, aver- age, 183.5. Food: Minnow remains, 50; Daphnia, 50. Grand summary for IQI4, 1915, and igi6. — Number examined, 115. Length: Maximum, 280; mini- mum, 25; average, 99.9. Food: Tadpoles, 0.3; fish eggs, 3; insect larvae, 34.7; insect pups, 1.7; adult insects, 1.8; mites, 0.1; amphipods, 24.5; Entomostraca, 25.8; molluscs, 3.8; oligochaetes, 0.4; pro- tozoans, -f ; plant remains, 0.8; alga, 0.7; silt and debris, i.i. The perch apparently feeds mostly on insects (38.2 per cent), amphipods (24.5 per cent), and ento- mostracans (25.8 per cent). Even large adults often have nothing in the alimentary canal except a great number of cladocerans. Forbes and Richardson (1908) stated that the perch is wholly carnivorous. Its food in rivers consisted of fish, molluscs, insect larvae, amphipods, shrimps, isopods, and cra^-fishes, and of fish and cra>-fish in lakes. Hankinson (1908) found midges in all stages of development, craj-fish, insects and larvae, snails, leeches, and entomostracans. Tracy (igio) reports small fishes, insects, etc. Reighard (1915 1 found the perch in Douglas Lake eating each other. All these observations show that the perch is a versatile feeder. At any age it may feed largely on entomostracans, insects, molluscs, or almost anything else that is edible. Percina caprodes (Rafinesque) var zebra Agassiz, log-perch. Data for igi4 (Pearse, 1915, Boekichthysfusiformis). Station 24; October 3; number examined, 7. Average length, 65.6. Food: Insect larva, 84; adult insects, 6.7; amphipods, 2.4; ostracods, o. i ; cope- pods, 0.3; cladocerans, -f; silt and debris, 6. Station 23, in rapids; April 28, 1915; number examined, 14. Length: Maximum, 94; minimum, 60; average, 76.3. Food: Fish eggs, 51.6; Chironomus larvae, 5.3; Hydropsyche altemans larvae, 10.3; Hyalella, 14.2; Cyclops, 0.2; leech, 1.8; plant remains, 4.8; filamentous alga;, 3.4; silt and debris, 7.8. Station 24; July 2; number examined, 2. Lengths: 79, 63. Food: Chironomus viridis larvae, 5; C. lobiferus lar\'a, 5; C. tentans larvae, 7.5; Protenthes culiciformis larvae, 4; Cricotopus trifasciatus larva;, 27.5; May-fly nymphs, 3.5; Ecdyurus maculipennis nymphs, 1.5; Callibaetis nymphs, i; Crico- topus trifasciatus pupa;, 15; Chironomus lobiferus pupae, 10; C. tentans pupae, 5; leech, 15. Summary. — Food: Insect larvae, 55; pupae, 30; leech, 15. Station 23, on beach at mouth of river; August 19; number examined, i. Length: 44. Food: Chironomus viridis larvae, 25; C. flavicingula lars^ae, 15; C. tentans larv'ae, 50; C. tentans pupae, 6; cladoc- erans, 4. FOOD OF THE SHORE FISHES OF CERTAIN WISCONSIN LAKES. 27 1 Station 24; September 17; number examined, i. Length: 56. Food: Chironomus digitatus larvae, 95; May-fly nymphs, 5. Station 23, in rapids by locks; June 20, 1916; number examined, 2. Lengths: 100 and 98. Food: Simulium larvse, 42.5; diptera pupae, 25; Hyalella, 32.5. Grand summary for IQI 4, IQ15, and IQ16. — Number examined, 27. Length: Maximum, 100; min- imum, 44; average, 72.9. Food: Fish eggs, 27.8; insect larvae, 45.5; insect pupae, 3.7; adult insects, 1.7; amphipods, 6.6; Entomostraca, 0.3; leeches, 2; plant remains, 3.4; algae, 1.7; silt and debris, 5.7. This summary- shows that the log-perch fed mostly on insects and fish eggs. This agrees in part with the results of Forbes and Richardson (1908), who found that two-thirds of the food was insects, but the other third mostly entomostracans. This fish evidently feeds by choice on the aquatic insects and their ]ar\-£e found among vegetation. PLmephales notatus (Rafinesque). Blunt- nosed minnow. Station 15; November 21, 1914; number examined, 4. Lengtli: Maximum, 32.2; minimum, 23.6; average, 27.7. Food: Cyclops, 22.5; Chydorus sphaericus, 2.5; cladoceran fragments, 62.5; filamentous algs, 12.5. Station 19; December 3; number examined, 4. Length: Maximum, 30; minimum, 26.4; average, 28.4. Food: Chironomid larvae, 25; Cyclops, 10; Chydorus sphaericus, 15; Eurycercus lamellatus, 22.5; cladoceran fragments, 25; diatoms, 2.5. Summary. — Food: Copepods, 10; cladocerans, 62.5; algae, 2.5. Station 23; June 14, 1915; number examined, i. Length: 70. Food: Chironomus tenellus adults, 95 ; Cyclops, 5. Station 27; June 17; number examined, 29. Length: Maximum, 62; minimum, 34; average, 46. Food: Orthocladius sordidellus larvae, 9; Probezzia pallida larvae, 2.6; Chironomus lobiferus larvae, 4; C. 1. pupae, 7.1; adult midges, 6; ostracod, -f ; Cyclops, 0.2; Chydorus sphaericus, 3; Bosmina longiros- tris comuta, 30.7; ephippial eggs, 0.2; Eiuycercus lamellatus, 0.5; cladocerans, o.i; filamentous algae, 8.2; plant remains, 1.9; fine debris and silt, 24.2. Summary. — Food: Insect larvae, 15.6; pupae, 7.1; adult insects, 6; ostracods, +; copepods, 0.2; cladocerans, 34.5; algae, 8.6; plants, 1.9; silt and debris, 24.2. Station 28; June 17; number examined, 10. Length: Maximum, 36.5; minimum, 26.2; average, 30.2. Food: Chironomid larvae, 19.5; Chironomus lobiferus pupae, 4.1; mite, o.i; ostracods, 0.5; Cyclops, 2.1; oligochaetes, 6; flagellates, 0.1; diatoms, 0.5; Pediastrum, 0.1; filamentous algae, 49.8; plant remains, 0.2; silt and debris, 17. Summary. — Food: Insect larvae, 19.5; pupae, 4.1; mite, 0.1; ostracods, 0.5; copepods, 2.1; oligo- chaetes, 6; protozoans, 0.1; algae, 50.4; plants, 0.2; silt and debris, 17. Station3; June24; number examined, 3. Lengths: 43,41.7,32.5. Food: Chironomid larvae, 1.7; Orthocladius sordidellus pupae, 1.3; adult midges, 3.3; Chydorus sphaericus, 2.7; oligochaetes, 28; Clos- terium, 0.3; filamentous algae, 50; plant remains, 0.3; silt and debris, 12.3. Station 24; July 2; number examined, 2. Lengths: 48.5, 28. Food: Chironomid larvae, 25; chironomid pupae, 25; ostracods, 0.5; oligochaetes, 49; sand, 0.5. Station 23; July 3; number examined, i. Length: 58.5. Food: Chydorus sphaericus, i; filamen- tous algae, 60; silt and debris, 39. Station 23; July 9; number examined, 4. Length: Maximum, 54.5; minimum, 34; average, 44.6. Food: Chironomid larvae, 12.5; Chironomus fulviventris larvje, 0.5; C. tentans larvae, 0.8; Chy- dorus sph^ricus, 0.1; oligochaetes, 39.9; desmids, 1.2; filamentous algae, 29; silt and debris, 16. Summary. — Food: Insect larvae, 13.8; cladocerans, 0.1; oligochaetes, 39.9; algae, 30.2; silt and d6bris, 16. Station 5; August 18; number examined, 2. Lengths: 41, 35. Food: Chironomid larvae, 5; ostracods, 3.5; Cyclops, 2.5; Eurycercus lamellatus, 4; plant remains, 2.5; silt and debris, 82.5 Grand summary. — Number examined, 60. Length: Maximum, 70; minimum, 23.6; average, 40. Food: Insect larvae, 14.5; pupae, 5.8; adult insects, 4.5; ostracods, 0.3; copepods, 2.6; cladocerans, 25.1; oligochaetes, 7; algae, 19.3; plant remains, 0.9; silt and d6bris, 20. As would be expected from its long intestine, the blunt-nosed minnow eats a good deal of silt, bottom debris, and plants, though entomostracans and insects constitute more than half of its food. Certain individuals had taken foods as follows: Chironomus lobiferus pupae, 100; Bosmina longirostris 272 BULLETIN OF THE BUREAU OF FISHERIES. comuta, icxj; oligochaetes, 98; filamentous algae, 90; silt and debris, 100. These figures show that the minnow is a versatile feeder. The food in the stomach has always been chewed into fine pieces. Forbes and Richardson (1908) stated that the stomach of this species is commonly packed with mud containing filamentous algae and miscellaneous vegetable debris. Hankinson (1908) found the food varies greatly, but consists chiefly of small organisms taken from the bottom, from water plants, and from the water. These fish eat the eggs of the black bass, Johnny darter, miller's thumb, and sunfish. Sometimes they devour the newly hatched fry of their own species. Other foods mentioned consisted of filamentous algae, desmids, entomostracans, and insects. Reighard (1915) said tehis minnow is a "mud cater. " Pimephales promelas (Rafinesque.) Black-head minnow, Sathead. Station 17; September 18, 1915; number examined, 3. Lengths: 51, 50.5, 43. Food: Tanytarsus gregarius larvae, 79.3; mites, 1.6; amphipods, 0.3; Cyclops, 2.6; oligochaetes, 6; diatoms and other algae, 1.3; sand and debris, 8.3. Pomoxis sparoides (Lac6pMe). Black crappie, calico bass, silver bass. Station 17; April 10 and 13, 1915; number examined, 4. Lengths: 145,130,132,75. Food : Minnows, 12.5; chironomid larvae, 1.2; May-fly nymphs, 22.5; Siphlurus nymphs, 0.7; Enallagma hageni, 12.5; Smithiurus, 0.5; Corixa adults, 24.5; Hyalella, 8.7; Chydorus sphaericus, 0.2; plant remains, 11.5; fil- amentous algae, 2.3; fine debris, 1.2. Summary. — Food: Fish, 12.5; insect larvae, 36.9; adult insects, 25; amphipods, 8.7; cladocerans, 0.2; plants, 11.5; algae, 2.3; debris, 1.2. Station 21, along south shore of Lake Wingra; number examined, 4. Lengths: 154, 140, 70, 53. Food: Fish, 6.2; Chironomus nigricans larvae, o.i; Tanypus monilis larvae, +; Probezzia larvae, 10; caterpillar, 11; Bstis nymphs, 4.5; Chironomus fulviventris pupae, 38.5; mites, 1.3; Dikerogammarus fasciatus, 0.5; Hyalella, 10; ostracods, 2.5; Cyclops bicuspidatus, 21.1; Chydorus sphaericus, 1.8; filamentous algae -i-. Summary. — Food: Fish, 6.2; insect larvae, 24.3; pupae, 38.5; mites, 1.3; amphipods. 10.5; ostracods, 2.5; copepods, 21. i; cladocerans, 1.8; algae, -1-. Station 17; August 24; number examined, i. Length: 186. Food: Caenis diminuta nymph, 8; moth, 8i; Eurycercus lamellatus, i; WolfTia, 10. Station 6; August 25; number examined, i. Length: 100. Food: Chironomus viridis lar\'ae, 10; C. lobiferus pupae, 10; Hyalella, 15; Simocephalus, 61.9; Ceratophyllum, 3: seed, o.i. Station 28; September 15; number examined, 3. Lengths: 116, 105, 104. Food: Fish, 79; Chiron- omus vu-idis larvae, 0.3; Caenis diminuta nymph, i; Corixa adult, ^.y, Cyclops, 0.3; Chydorus, 0.2; Daphnia, 11. 7; plant remains, 3.3. Station 24; September 17: number examined, i. Length: 45. Food: Insect larvae, 15; chironomid larvae, 10; Hyalella, 60; Cyclops, 3; Chydorus sphaericus, 2; Daphnia, 10. Station 22; October 27; number examined, 36. Length : Maximum , 48; mininum, 36; average, 40.4. Food: Fish, 0.3; insect larvae, i; chironomid larvae, 3.6; Tanypus gregarius larvae, 9; Bastisca nymph, 4.3; Chironomus lobiferus pupae, 0.4; SmithiiuTis, 0.6; moth, 0.4; adult midges, 2.5; Probezzia pallida adults, 5.8; Cordyliu-a adults, 0.6; Hyalella, 3.5; ostracods, 21.7; Diaptomus, 0.2; Canthocamptus, 20.7; Cyclops, 18.6; Chydorus, 1.5; Pleiu-oxus, i; Simocephalus, +; seeds, 0.4. Summary. — Food: Fish, 0.3; insect larvae, 17.9: pupae, 0.4; adult insects, 9.9; amphipods, 3.5: ostra- cods, 21.7; copepods, 29.5; cladocerans, 1.5; plants, 0.4. Station 26; November 27; number examined, 7. Length: Maximum, 221; minimum, 160; average, 184. 1. Food: Insect larvae, 0.8; Chironomus viridis larvae, 8.9; C. tentans larvae, 4.3; Baetisca nymphs, 2.1; Ischnura verticalis nymphs, 2.1; Canthocamptus, -|-; Daphnia, 54.7; Leptodora, 27.1. Summary. — Food: Insect larvae, 18.2; copepods, +; cladocerans, 81.8. Station 18; April 29, 1916; number examined, 3. Length: Maximum, 188; minimum, 159: average, 172.3. Food: Minnow, 13.3; Chironomus fulviventris larvae, 3.3; C. lobiferus larvae, z-3'. Ephemerella sp. nymphs, 1.6; Celithemiseponina nymph, 6.6; Setodis grandis larvae, 0.3; Corixa adult, 1.6; Hyalella, 69; filamentous algae, 0.3; leaf 0.1; plant remains, 0.1. Summary. — Food: Fish, 13.3; insect larvae, 15. i; insect adults, 1.6; amphipods, 69; plants, 0.5. FOOD OF THE SHORE FISHES OF CERTAIN WISCONSIN LAKES. 273 Station 18; May 13; number examined, i. Length: 200. Food: Chironomus fulviventris larvae, S; Notonecta nymphs, i; Chironomus decorus pupae, i; Corixa adults, 3; adult beetles, 28; Hyalella, 50; Eurycercus, 2; filamentous algae, 10. Summary. — Food: Insect larvae, 6, insect pupae, i; insect adults, 31; emphipods, 50; Entomostraca, 2; plants, 10. Station 28; May 30; number examined, 2. Length: Maximum, 183; minimum, 170; average, 176.5. Food: Fish eggs, i; Chironomus fulviventris larvae, 12.5; C. lobiferus larvae, 16.5; C. decorus larva, 2.5; Probezzia glaber larvae, 5; Notonecta nymphs, 2.5; Chironomus sp. pupae, 35; C. fulviventris pupae, S; C. decorus pupae, 5; mites, 10; Hyalella, 10. Summary. — Food: Fish eggs, i; insect larvae, 39; insect pupae, 45; mites, 10; amphipods, 10. Station 26; July 13; number examined, 3. Length: Maximum, 183; minimum, 142; average, 169.3. Food: Minnow, 3.5; Chironomus lobiferus larvae, 25; Enallagma hageni nymphs, 3.^; Chironomus sp. pupae, 12.6; Corixa adults, 0.3; Hyalella, 0.3; Daphnia, 6.3; D. pulex, 16.6. Summary. — Food: Fish, 3.5; insect larvae, 28.3; insect pupjE, 12.6; insect adults, 0.3; amphipods, 0.3; cladocera, 22.9. Grand summary for igiS and IQ16. — Number examined, 66. Length: Maximum, 221; minimum, 35; average, 90.5. Food: Fish eggs, o.i; fish, 7.1; insect larva, 19. i; insect pupae, 4.6; adult insects, 8.8; mites, 0.4; amphipods, 10.6; Entomostraca, 47.4; plants, 1.5; silt and debris, +. The black crappie depends on entomostracans (47.4 per cent), insects (33.5 per cent), amphipods, and small fish for its food. Its form fits it to live among aquatic plants, and in general its food comes from such situations. The largest fish examined (November 27, 1915), however, had eaten over three- foiuths pelagic entomostracans. Forbes and Richardson (1908) stated that the crappies are strictly car- nivorous, living mainly on insects, crustaceans, and fish. Roccus chrysops (Rafinesque). White bass. Station 15; June 6, 1915; number examined, i. Length: 165. Food: Chironomus decorous larvae, 40; Protenthes choreus larvae, 39.9; Corethra larvae, 10; Hyalella, o.i. Summary. — Food: Chironomid larvae, 99.9; amphipods, 0.1. Station 5; August 18; number examined, i. Length: 29. Food: Cyclops, 65; Bosmina longirostris comuta, 35. Station 5; August 25; number examined, i. Length: 35. Food: Corixa adults, roo. Station 5; August 25; number examined, 2. Lengths: 35, 29. Food: Chironomus adults, 5; Cyclops, 60; Bosmina longirostris comuta, 30; Simocephalus, 3. Summary. — Food: Adult insects, 5; copepods, 60; cladocerans, 35. Station 5; August 30; number examined, 6. Length: Maximum, 44; minimum, 32; average, 37.9. Food: Insect eggs, 20; chironomid larva, 0.8; Chironomus decorus larvae, 1.6; Batisca nymphs, 13. i; Enallagma hageni nymphs, 6.6; Chironomus lobiferus pupa, 10; C. viridis pupa, 1.6; HyaleUa, 9.1; Cyclops, 27; Cyclops serrulatus, 6.6; chydorids, 1.8; Simocephalus, i. Summary. — Food: Insect larva, 42.1; pupa, 11. 6; amphipods, 9.1; copepods, 33.6; cladocerans, 2.8. Station 5; September 2; number examined, i. Length: 33. Food: Chironomus decorus larva, 5; Protenthes culiciformis pupa, 5; Hyalella, 15; ostracods, 5, Cyclops, 65; cladocerans, 5. Station 5; September 22; number examined, i. Length: 220. Food: Fundulus diaphanus menona, 55; Chironomus decorus larva, 8; Corethra larva, 20; Chironomus decorus pupa, 8; C. d. adult, 7; Leptocerus dilutus adult, 2. Summary. — Food: Fish, 55; insect larva, 28; pupa, 8; adult insects, 9. Station 15; depth, 13 meters; November 13; number examined, i. Length: 145. Food: Daphnia, 60; Leptodora, 40. Grand summary. — Number examined, 14. Length: Maximum, 220; minimum, 29; average, 65.6. Food: Fish, 4.2; insect eggs, 8.6; larva, 22.2; pupa, 5.8; adult insects, 8.4; amphipods, 5; ostracods, 0.4; copepods, 29.6; cladocerans, 16.3. The white bass feeds primarily on entomostracans (46.3 per cent) and insects (45 per cent). The adults eat insects more than anything else, but also take fish. Forbes and Richardson (1908) mentioned insects, crustaceans, and fishes as constituents of the food of this species. Two adults examined by the writer in 1914 were filled with adult midges. 274 BULLETIN OF THE BUREAU OF FISHERIES. Salmo irideus (Jordan and Evermann). Rainbow trout. Station 30; August 26, 1915; number examined, i. Length: 126.5. Food: Chironomus fulvi- ventris larvae, 5; Tanypus decoloratus larvse, 5; Ps^choda larvse, 5; Phr>-ganea lar\'Ee, 8; Odontomyia lar^'se, 10; Chironomus fulviventris pupae, i; C. lobifcrus pupae, 2; leptid adult, 4; Peltodytes 12-puncti- pennis adult, 3; Julus, 10; Garamarus limnaeus, 42; Physa, 5. Sunimary. — Food: Insect larvae, 33; pupae, 3; adult insects, 7; millipeds, 10; amphipods, 42; snails, 5. Salvelinus fontinalis (Mitchill.) Brook trout. Station 30; August 26, 1915; number examined, 18. Length : Maximum , 160; minimum, 87; average, 103.2. Food: Dipterous lar^-Ee, 3.5; Chironomus fulviventris lar\'£e, 13.2; Tanypus decoloratus larvae, i; Psychoda larvae, 0.3: Phrj'ganea larvae, 11. 5; Agabus larvae, 1.8; Odontomyia larvae, i.i; Dytiscus hybri- dus larvae, 0.5; Dixa larvae, i; Chironomus fulviventris pupae, 18.2; C. lobiferus pupae, 0.2; leptid flies, 0.8; Peltodytes 12-punctipennis adult, 0.2; Agabus adult, i.i; Corixa adults, 0.3; Camponotus adult, o. i; Melanoplus femurnibriim adult, 3; jassid bug, o.i; Julus, 0.4; Limnesia histrionica, 0.4; Gammarus limnaeus, 35.5; Asellus communis, 0.5; Procellio rathkei, 0.8; Physa, 1.4; seeds, +; Polygonium seeds, 0.1. Summary. — Food: Insect larvae, 33.0; pupae, 18.4; adult insects, 5.6; millipeds, 0.4; mites, 0.4; amphipods, 35.5; aquatic isopods, 0.5; terrestrial isopods, 0.8; snails, 1.4; plant seeds, o.i. This trout feeds largely on insects and other arthropods. The Fish Manual (1900) has this state- ment: "The brook trout has a voracious appetite and takes advantage of every opportunity to satisfy it, except in the spawning season, when it takes no food at all. It is strictly a carnivorous fish, its food consisting chiefly of Crustacea, mollusca, and various forms of insects and worms. When pressed with hunger, it does not hesitate to devour its own kind. " Tracy (1910) said this fish will eat nearly any small living creature — insects, fish, its own eggs and young, tadpoles, newts, etc. Scbilbeodes gyrinus. (Mitchill.) Tadpole cat. Data for jgi4 (Pearse, 1915). — Station 4; August 6; number examined, 5. Length: Maximum, 26.8; minimum, 17.6; average, 22.3. Food: Insect larvae, 8; adult insects, 4; Hyalella, 0.4; ostracods, 0.4; copepods, 62; cladocerans, 1.6; algae, 4.2; silt and debris, 15. Station 5; May 12; number examined, 14. Length: Maximum, 76; minimum, 30.3; average, 42.8. Food: Insect larvae, 1.4; chironomid larvae, 2; Chironomus lobiferus larvae, 7; C. fulviventris larvae, 1.8; Pelopia monilis larvae, 3; Orthocladius soldidellus larvae, 2; May-fly nymphs, 12; Baetis pygmaea nymphs, 10; Callibaetis nymphs, 10; Corixa nymphs, 1.3; Neuronia postica pupae, 2.4; Chironomus lobiferus pupae, 2; grasshopper, 1.4; Enallagma antennatum adults, 5; adult dipteron, 2; Hyallella, 7; ostracods, 6.5; Cyclops, 2; chydorus sphaericus, 11; Simocephalus, 0.5; Eurycercus lamellatus, 6.3; oligochaetes, 1.4; fine debris, 2. Summary. — Food: Insect nymphs and larvae, 50.5; pupae, 4.4; adult insects, 8.4; amphipods, 7; ostracods, 6.5; copepods, 2; cladocerans, 17.8; oligochaetes, 1.4; debris, 2. Station 5; June 1; number examined, g. Length: Maximum, 45; minimum, 38.5; average, 42.6. Food: Chironomus lobiferus larvae, 4; Orthocladius sordidellus larvae, 16; damsel-fly n^-mphs, i.i; beetle larvae, 33.2; Naucoris nymphs, 8.3; Chironomus lobiferus pupae, 2.7; C. decorus pupae, 7.2; Odontomyia pupae, 0.5; Lachnosterna adult, i.g; ostracods, 8.5; Cyclops, 9; oligochaetes, 5.5; filamentous algae, 0.1; fine debris, 2. Summary. — Food: Insect larvae, 62.6; pupae, 10.4; adult insects, 1.9; ostracods, 8.5: copepods, 9; oligochaetes, 5.5; filamentous algae, 0.1; fine debris, 2. Station 5; August g; number examined, 2. Lengths: 21.5, 21. Food: Protcnthes culiciforrais larvae, 15; Callibaetis nymphs, 17.5; mite, i; Hyalella, 12.5; ostracods, i; Chydorus sphaericus, 0.5; Campto- cercus, 17.5; oligochaetes, 12.5; seeds, 17.5; fine debris, 5. Summary. — Food: Insect larvae, 32.5; mites, i; amphipods, 12.5; ostracods, i; cladocerans, 18; oligochastes, 12.5; seeds, 17.5; debris, 5. Near Station 5, on lake shore; August 18; number examined, 14. Length: Maximum, 63; minimum, 14; average, 25.8. Food: Chironomus lobiferus lar\-ae, 1.4; damsel-fly nymphs, 1.4; May-fly nymphs 0.7; EcdyiUTis maculipennis nymphs, 1.3; Caenis diminuta nymphs, 27.7; Hyalella, 6.7; ostracods, i, Camptocercus, 0.2; cladocerans, 0.2; Planorbis, 0.3; oligochxtes, 42.7; seeds, 15; duckweed, 1.4. .Summary. — Food: Insect larvae, 32.5; amphipods, 6.7; ostracods, i; cladocerans, 0.4; snails, 0.3; oligochaetes, 42.7; plants, 16.4. FOOD OF THE SHORE FISHES OF CERTAIN WISCONSIN LAKES. 275 Station 5; August 18; number examined, 10. Length: Maximum, 27.8; minimum, 18; average, 22.3. Food; Chironomus fulviventris larv'je, 3; C. digitatus larv^, 1.5; Tanypus decoloratus larvae; 2.5; Orthocladius sordidellus larva;, 2.5; May-fly nymphs, 3.5; Batisca nymphs, 1.5; Csnis diminuta nymphs, 10.5; Enallagma antennatum adtilt, 3.5; Hyalella, 27.3; ostracods,3; Cyclops, 2; Chydorus, phaericus, 0.5; Simocephalus, 0.7; Camptocercus, 2.3; oligochaetes, 31.4; seeds, i; Myriophyllum, 3; sand, 0.3. Summary. — Food: Immatiu-e insects, 25; adult insects, 3.5; amphipods, 27.3; ostracods, 3; cope- pods, 2; cladocerans, 3.5; oligochaetes, 31.4; plants, 4; sand, 0.3. Station 5; September 15; number examined, i. Length: 59. Food: Insect larvje, 7; Hyalella, 55; ostracods, 8; cladocerans, 15; fine debris, 15. Grand summary for I gi 4 and I gi^. — Number examined, 55. Length: Maximum, 76; minimum, i4.' average, 34.3 Food: Insect larva, 36; pupae, 4.4; adult insects, 3.6; mites, -f; amphipods, 10.3; ostracods, 4; copepods, 7.9; cladocerans, 6.1; snails, o.i; oligochaetes, 18.3; plants, 5.9; alga, o.i; silt and debris, 3. The tadpole cat feeds chiefly on insects (44 per cent), oligochaetes (18.3 per cent), and small crus- taceans (28.3 per cent). The items in its diet show that it gets its food on the bottom and among aquatic plants. The smaller individuals apparenly depend upon crustaceans and oligochaetes, larger fishes turn more to insects. Forbes and Richardson (1908) found this species feeding on amphipods isopods, entomostracans, insect larvae, and small fish. Hankinson (1908) found insect fragments. Stizostedion vitreiun (Mitchill). Wall-eyed pike, pike perch, jack-salmon. Station 28; September 15, 1915; number examined, 2. Lengths: 448, 425. Food: Fish, 100. Station 29; November 14; number examined, 9. Length: Maximum, 520; minimum, 375; average, 441. Food: Rana pipiens, 11. i; fishes (one a sunfish), 88.9. Grand summary. — Number examined, 11. Average length: 440. Food: Frogs, 9.1; fishes, 90.9. Forbes and Richardson (1908) stated that this species feeds chiefly on fish, sometimes varying its diet with crayfishes. Umbra limi (Kirtland). Mud minnow, mudfish. £>ato/or jpz4 (Pearse, 1915). — Number examined, 60. Average length: 33.5. Food: Insect larvae, 21; adult insects, 16.3; mites, 0.3; amphipods, +; ostracods, 33.9; copepods, 0.5; cladocerans, 1.2; snails, 0.7; Sphaeridae, 0.2; oligochates, i; nematodes, 0.7; protozoans, 0.1; plant remains, 1.9; algae, 15. i. Station 21; April 28, 1915; number examined, 9. Length: Maximum, 80; minimum, 31; average, 51. 1. Food: Insect larvae. 3; Platyphylax designatus larvae, 4.5; Chironomus viridis larvae, i; Tanypus decoloratus larvae. zy< Pelopia flavifrons larvae, 3.3; Odontomyia larvae, 4.5; Haliplus adult, 0.2; Corixa adult, 4; mites, 2; Hyalella, 12; Dikerogammarus fasciatus, 26; Cyclops, 0.3; C. viridis, 5.8; C. fimbriatus, 5; cladocerans, 0.3 ; Chydorus sphaericus, 0.5; leech, 5.5; oligochstes, 12; plant remains, 1.5; Pleurococcus, 2.5: diatoms, 0.5; silt, i; fine debris, i. Summary. — Food: Insect larvae, ig. 6; adult insects, 4.2 ; mites, 2; amphipods, 38; copepods, 11. i; cladocerans, 0.8; leech, 5.5; oligochaetes, 12; plants, 1.5; algae, 3; silt and debris, 2. Station 16; May 15; number examined, i. Length: 68.7. Food: Adult midges, 10; earthworm, 79; diatoms, i; silt and debris, 10. Station 5; June i; number examined, 4. Lengths: 68, 60, 54, 49.5. Food: Insect larvae, 11; chironomid larvae, 0.5; Chironomus lobiferus larvae, 2.2; Orthocladius sordidellus larvae, 20.4; chiron- omid pupae, 9.6; Probezzia pups, 0.6; adult weevil, i; adult midges, 6.2; ostracods, 4; Dikero- gammarus, 1.2; Cyclops,:; Chydorus, 0.2; Eurycercus lamellatus, 1.2; Physa, 1.7; seeds, 14; Wolffia, 2.5; plants, 0.2; filamentous algae, 0.3; Pleurococcus, 20; silt and debris, 2.5. Summary. ^Pood: Insect larvae, 34.1; pupae, 10.2; adult insects, 7.2; ostracods, 4; amphipods. 1.2; copepods, i; cladocerans, 1.4; snails, 1.7; plants, 16.7; algae, 20.3; silt and debris, 2.5. Station 21; June 12; number examined, 10. Length: Maximum, 179; minimum, 35; average, 63.9. Food: Insect larvae, 1.5; chironomid larvae, 0.7; Chironomus larvae, i; Chironomus fulviventris larvae, 25; Palpomyia longipennis larvae, 3; Cricotopus trifasciatus larvae, 2.3; C. t. pupae. 8.7; chiron- omid pupae, 4.3; adult midges, 11; mites, 0.3; ostracods, 0.1; Dikerogammarus, 26.9; Cyclops, 2.7; Physa, 0.8; Pleurococcus, 3.5; silt and debris, 7. 276 BULLETIN OF THE BUREAU OF FISHERIES. Summary. — Food: Insect larvae, 33.7; pups, 12. i; adult insects, 11; mites, 0.3; ostracods, o.i; amphipods, 26.9; copepods, 2.7; snails, 0.8; algae, 3.5; silt and debris, 7. Station 25; June 17; number examined, 10. Length: Maximum, 84; minimum, 42.5; average, 49.3. Food: Chironomid larvae, 2; Libellula luctuosa nymphs, 10; chironomid pupae, 2.5; Haliplua adults, 2.5; Corixa adults, 5; mites, 3; ostracods, 32.2; Cyclops, 7; Chydorus, 1.5; Simocephalus, 4.6; Planorbis, 5.5; Limnaea, 3.5; oligochaetes, 6 ; filamentous algae, 1.2; Pleurococcus, 9; silt and dfebris, 4.5. Summary. — Food: Insect larvae, iz; pupae, 2.5; adult insects, 7.5; mites, 3; ostracods, 32.2; copepods, 7; cladocerans, 6.1; snails, g; oligochaetes, 6; algae, 10.2; silt and debris, 4.5. Station 28; Julys; number examined, i. Length: 47.5. Food: Oxyethira larvae, 10; caiabid- beetle larvae, 10; Odontomyia vcrtebrata larvae, 10; ostracods, 5; Hyalella, 60; Cyclops, 5. Summary. — Food: Insect larvae, 30; ostracods, 5; amphipods, 60; copepods, 5. Station 25, in ditch along road; number examined, 14. Length: Maximum, 25.2; minimum, 15.1; average, 20.6. Food: Insect larvae, 0.3; chironomid larvae, 5; Chironomid tentans larvae, 5.3; Pal- pomyia longipennis larvas, 0.3; Cricotopus trifasciatus larvae, 7; Caenis diminuta nymphs, 0.7; beetle lan-ae, 3.5; dascyllid larvae, 8.5; midge pupa, 3.5; adult bug, 1.8; insect remains, 0.3 ; adult midges, 4.6; Naucoris adult, 4.4; Collembola, 0.8; mites, 0.3; Hermannia bistriata, 5.6; ostracods, 12.2; Cyclops, 11; Canthocamptus, i; chydorid, o.i; Planorbis, 2; Limnaea, 5.2; oligochaetes, 7; rotifers, 1.3; Oscillaria, 0.7; Vol vox and other algae, 0.3; filamentous algae, 0.1; Pleurococcus, 4.3; sand, 1.4. Summary. — Food: Insect larvae, 30.6; pupae, 3.5; adult insects, 11. 9; mites, 5.9; ostracods, 12.2; copepods, 12; cladocerans, 0.1; snails, 7.2; oligochaetes, 7; rotifers, 1.3; algse, 54; sand, 1.4. Station 23; August 14; number examined, i. Length: 51. Food: Hyalella, 25; Cyclops, 1; Chydorus, i; plant remains, 73. Grand summary for JQ14 and JQI5. — Number examined, no. Length: Maximum, 179; minimum, 15. i; average, 41.9. Food: Insect larvae, 21.9; pup.'E, 2.1; adult insects, 10.9; spiders, 0.1; mites, 1.2; amphipods, 6.5; ostracods, 23.1; copepods, 3.6, cladocerans, 1.3; snails, 2.3; Sphaeridae, 0.1; oligochaetes, 2.9; leeches, i.i; nematodes, 0.4; rotifers, 2; protozoans, 0.2; plants, 2.5; algae, 11. i; silt and ddbris, 1.4; unidentified, 3.8. The mud minnow is a rather versatile feeder, with the chief constituents of its food, insects (35 per cent), entomostracans (31.3 per centi, and vegetation (13.6 per cent). Forbes and Richardson (1908) found that Wolffia and unicellular algae formed three-fourths of the food of this species, insects and crustaceans making up the rest. Hankinson (1908) reported entomostracans, algae, mites, midge larvae, snails, and insects. III. FOODS UTILIZED BY FISHES. DIFFERENT SPECIES OF FISHES HAVE DIFFERENT FOOD HABITS. Table i shows the different kinds of food eaten by the shore fishes of lakes. If more complete information is desired it may be obtained from the preceding section, where the food of the fishes in each catch is given in considerable detail. Most fishes are not indiscriminate feeders, but select specific things from the avail- able food supply. A good illustration of this point is furnished by the fishes caught to- gether at station 18, July 3, 1915. The foods taken by each of these fish are shown in Table 3, and it will be noted that the different species were about the same average size. The black bass is the most versatile, having taken 21 different items of food, the blue- gill comes next with 16, the shiner has 14, and the top minnow 1 1. Each fish has taken a different item in the largest quantity — i. e., the black bass, 25 per cent Enallagma antennatum nymphs; the top minnow, 49 per cent Hyalella; the bluegill, 47 per cent Eurycercus; and the shiner, 42.6 per cent Daphnia longispina hyalina. All the fishes had eaten Eurycercus, which must have been abundant, and two had taken Hyalella. The other two items taken in largest amount {Daphnia hyalina and Enallagma antennatum) were each eaten by only a single species. In Table 4 (which resembles Table 3) three of the species have eaten more fish than any other kind of food, but the fourth has taken none. Table 2 shows the Johnny darter feeding largely on chironomid larvae and oligo- FOOD OF THE SHORE FISHES OF CERTAIN WISCONSIN LAKES. 277 chaetes; the bream and white bass on Cyclops and other entomostracans ; the perch and black bass on the larger insect larvae, adult insects, and amphipods; the blunt-nosed minnow on mud; the tadpole cat on oligochaetes. An examination has been made of Tables 2, 3, and 4 and ten others similar to them. Each of these tables concerned four or more species of fishes captured at the same time and place. The following 22 species (506 individuals) appear one or more times in them : Ahramis crysoleucas , Ambloplites rupestris, Amiatus calva, Ameiurus mclas, Ameiu- rus nebulosus, Boleosoma nigrum, Caiosiomus comtnersonii, Cyprinus carpio, Esox lucius, Etheostoma iowcB, Fundulus diaphanus menona, Labidesthes sicculus, Lepomis incisor, Micropterus salmoides, Notropis heterodon, Perca flavescens, Percina caprodes, Pimephales notaius, Pomoxis sparoides, Roccus chrysops, Schilheodes gyrinus, and Umbra limi. The different figures in the bottom line of all tables were added to ascertain whether specific foods were Hkely to be eaten by one or more fish. The results were as follows: Items appearing once in any one table, 356; twice, 93; thrice, 45; four or more times, 11. This shows that, though fishes may feed on the available foods, different species captured at the same time and place have not eaten the same things. All things, then, indicate that fishes select food from their environment. In some cases the powers of selecting and rejecting are remarkable. A perch may have its whole alimentary canal packed full of Daphnias, when the surrounding water contains Daph- nias mixed with greater quantities of algse. Only the animal plankton is taken. The young sucker is able to take such minute living objects as Difflugia, Arcella, and rotifers from a muddy bottom, rejecting fine particles of silt. CLASSES OF FOODS UTILIZED BY FJ^HES. The foods found in fishes occurring along the shores of Wisconsin lakes fall into nine classes. In order of their importance these rank as follows: (i) Insect larvae, oligo- chaetes and leeches, 28.7 per cent; (2) entomostracans, 19. i per cent; (3) fishes and frogs, 13.8 percent; (4) insect pupae and adults, 11. 7 percent; (5) amphipods, isopods, and mites, 12.7 percent; (6) plants, including algae, 4.2 percent; (7) mud, silt, and fine debris, 2.6 per cent; (8) molluscs, 2 per cent; and (9) crayfishes, i.i per cent. The per- centages were obtained from the last line of Table i. In the follo%ving paragraphs fishes are arranged under each class in the order of their importance. Every species taking food in a particular class is not always recorded but they all appear in Table i. It must be remembered that there is a preponderance of young fishes in the data from' which these results are figured. An examination of more adults would doubtless increase classes 3, 6, 8, and 9. I. Fislies feeding upon insect larvcB, oligochcetes , a^id leeches. — Boleosoma nigrum, "jj.S per cent; Amsiurus melas, 59.6 per cent; Schilbeodes gyrinus, 57.9 per cent; Persina caprodes, 54 per cent; Catostomus commersonii, 51.5 per cent; Etheostoma flabellare, 50.5 percent; Ambloplites rupestris, 46 per cent; Cyprinus carpio, 42.5 per cent; Etheo- stoma iowcs, 38.6 percent; Micropterus dolomieu, 27-7 percent; Lepomis incisor, 35.7 per cent; Cottus ictalops, 35.3 per cent; Perca flavescens, 35.1 per cent; Roccus chrysops, 30.8 per cent; Ameiurus nebulosus, 30.2 per cent; Fundulus diaphanus tnenona, 26.4 per cent; Umbra limi, 25.9 percent; Eucalia inconstans, 24.1 percent; Micropterus sal- m^ides, 23.7 percent; Pimephales notatus, 21.5 percent; Pomoxis sparoides, 18.4 per cent; EupomoUs gibbosus, 16.2 percent; Notropis heterodon, 15 percent. 278 BULLETIN OF THE BUREAU OF FISHERIES. 2. Fislies jeeding upon entomostracans . — Ahraviis crysoleucas, 76 per cent; Pomoxis sparoides, 53.7 per cent; Notropis heterodon, 44.9 per cent; Ameuirus nehulosus, 42.1 per cent; Lebidesthes sicculus, 40.1 percent; Eucalia inconstans, 38.5 percent; Fundulus diaphanus menona, 36 percent; Umbra limi, 31.3 percent; Pimephales nctatus, 28 per cent; Lepomis incisor, 24.9 per cent; Micropterus salmoides, 18.1 percent; Schilbeodes gyrinus, 18 per cent; Perca flavescens, 16.9 per cent. 3. Fishes feeding upon fishes and frogs. — SHzostedion vitreum, 100 per cent; Amiaius calva, 90.1 per cent; Lepisosteus osseus, 88.8 per cent; Esox Indus, 84 per cent; Percina caf>rodes, (eggs) 27.8 per cent; Micropterus dolomieu, 14.7 per cent; Eupomotis gibbosus, (eggs) 9.4 per cent; Micropterus salmoides, 8.2 per cent; Pomoxis sparoides, 5.7 per cent; Perca flavescens, 3.5 percent; Roccus chrysops, 4.2 percent; Ambloplites rupestris, 2 per cent. 4. Fishes feeding upon insect pupae and adult insects. — Labidesthes sicculus, 44.6 percent; Micropterus dolomieu, 39.7 percent; Micropterus salmoides, 31.2 percent; Ambloplites rupestris, 23.3 percent; Eucalia inconstans, 18.1 percent; Roccus chry- sops, 14.2 per cent; Notropis heterodon, 14.1 per cent; Umbra limi, 13 per cent; Pomoxis sparoides, 12.7 percent; Eupomotis gibbosus, 10.3 percent; Pimephales notatus, 10.3 per cent; Ameiurus melas, 9.9 per cent; Cyprinus carpio, 9.6 per cent; Lepomis incisor, 9.2 per cent; Schilbeodes gyrinus, 9 per cent; Ameiurus nebulosus, 6.5 per cent; Fundulus diapfianus menona, 4.8 percent; Percina caprodes, 3.9 per cent ; Perca flavescens, 3 per cent. 5. Fishes feeding upon amphipods, isopods, and mites. — Coitus icialops, 59.1 per cent ; Etheostoma iowce, 58 per cent ; EtJieostoma flabcllare, 48 per cent ; Perca flavescens, 24.6 percent; Lepomis incisor, 15. i percent; Fufidulus diaphanus menona, 14. i per cent; Micropterus salmoides, 13.9 percent; Ameiurus nebulosus, 11.8 per cent; Schilbe- odes gyrinus, 10.3 percent; Eupomotis gibbosus, 9 percent; Cyprinus carpio, 8.7 per cent; Umbra limi, 7.8 percent; Poinoxis sparoides, 7.5 percent; Eucalia inconstans, 5.2 per cent; Boleosoma nigrum, 5.1 per cent; Roccus chrysops, 5 per cent; Percina cap- rodes, 4.6 per cent; Esox lucius, 2.5 per cent. 6. Fishes feeding upon plants, including algce. — Eupomotis gibbosus, 25.5 percent; Pimephales notatus, 20.2 percent; Notropis heterodon, 15.6 percent; Umbra limi, 13.6 percent; Ameiurus melas, 7.3 percent; Fundulus diaphanus menona, 6.4 per cent; Schilbeodes gyrinus, 6 percent; Lepomis incisor, 5.2 percent; Abramis crysoleucas, 4.5 per cent; Eucalia inconstans, 4.4 per cent; LabidestJies sicculus, 4 per cent; Amblo- plites rupestris, 3.3 per cent. 7. Fishes feeding upon m,ud, silt, and fine debris. — Pimepltales notatus, 20 per cent; Notropis heterodon, 6.5 percent; Ameriurus melas, 6.3 percent; Percina caprodes, 5.7 percent; Fundulus diaphanus menona, 4.2 percent; Eucalia inccmstans, 3.7 percent; Catostomus ccmimersonii, 3.6 percent; Boleosoma nigrum, 3.1 percent; Schilbeodes gyri- nus, 3 per cent. 8. Fishes feeding upon molluscs. — Eupomotis gibbosus, 25.8 percent; Cyprinus carpio, 6.9 per cent; Lepomis iiwisor, 4.5 per cent; Futuiulus diaphanus menona, 3.9 per cent; Ameiurus melas, 3.7 percent; Perca flavescens, 3.7 percent; Eucalia inconstans, 3.7 per cent; Etheostoma iowce, 3 per cent; Umbra limi, 2.4 per cent. 9. Fishes feeding upon crayfish. — Amploplites rupestris, 16. i per cent; Amiatus calva, 9.4 percent; .\meiurus melas, 6.1 percent; Micropterus saltnoides, 2.6 percent. FOOD OF THE SHORE FISHES OF CERTAIN WISCONSIN LAKES, 279 IV. ADAPTABILITY OF FOOD HABITS. ALTERNATIVE FOODS. Fish prefer certain foods and select from their environment. If the largest single items are picked out from the dietaries of the fishes shown in Table i, the following results are obtained: Nine species eat more dipterous larvae than any other single kind of food; six, amphipods; five, cladocerans; four, fishes; two, adult hemipterous insects (Corixa); two, Cyclops; and one species takes its chief food from gastropods, dipterous pupae, May-fly nymphs, and ostracods. The next question to be answered is: What will the different fishes eat if their favorite food is not available ? To answer this, the three foods taken in largest quantity (i. c, first, second, and third choice) were selected for each of the 32 species shown in Table i. For example, the golden shiner, Ahramis crysoleucas , ate 57.6 per cent cladocerans, 16.5 per cent copepods, 5.7 per cent dipterous pupse, and other foods. This species was, therefore, put in a class "Cladocera — copepods — dipterous pupce." The classes and the number of species of fish taking the same three chief items of food were as follows : Diptera larvae — Copepoda — Cladocera 3 Cladocera — Diptera larvae — Amphipoda 3 Diptera larvae — Ostacoda — Copepoda 2 Cladocera — adult Diptera — Diptera pupae Cladocera — Copepoda — Diptera pupae Cladocera — Diptera larvae — algae Diptera larvae — crayfishes — Odonata nymphs Diptera larvae — Ostracoda — Cladocera Diptera larvas — Oligochaeta — plant remains Diptera larva — fish eggs — Trichoptera larvae Diptera larvae — Oligochaeta — Copepoda Fish — crayfish Fish — adult Diptera — Diptera larvae Fish — frogs Amphipoda — Ephemerida nymphs — Diptera larvae Fish — Amphipoda — Hemiptera nymphs or Sphaeridae Amphipoda — Diptera larvae — Millipeds Amphipoda — Diptera larvae^Trichoptera larvae Amphipoda — Diptera larvae — Diptera pupae Amphipoda — Diptera lar\'ae — Coleoptera larvae Gastropoda — plant remains — toad eggs Adult Hemiptera — Ephemerida nymphs — Diptera larvae Adult Hemiptera — Ephemerida nymphs — Cladocera Diptera pupae — silt and debris — Copepoda i Cladocera — silt and debris — algae i Ephemerida nymphs — Oligochaeta — Amphipoda i Ostracoda — Diptera larvae — Amphipoda i Thirty-two species of fishes thus show 27 classes. If only the two chief food items are considered, the number of classes is reduced to 19, as follows: Amphipoda — Diptera larvae 4 Diptera larvae — Copepoda 4 Diptera larvae — Ostracoda 3 Cladocera — Diptera larvae 3 Diptera larvae — Oligochaeta 2 28o BULLETIN OF THE BUREAU OP FISHERIES. Adult Hemiptera — Ephemerida nymphs 2 Cladocera — Copepoda i Cladocera — Adult Diptera i Cladocera — silt and d6bris i Diptera larvae— crayfishes i Diptera larvae — fish eggs i Fish — Odonata nymphs 1 Fish — frogs i Fish — Ephemerida nymphs i Amphipoda — Ephemerida nymphs i Amphipoda — Cladocera i Gastropoda — plant remains i Diptera pupae — silt and debris i Ephemerida nymphs — Oligochaeta i Both these comparisons give further support to the statements made under sec- tion III, showing that different kinds of fishes have specific preferences for certain foods. Nine species make their chief food the larvae of dipterous insects, which are far more abundant than anything else. When these eat something different from their favorite food, they do not all take the same kind of food but select five to seven new things. It is difficult to group fishes into large classes on the basis of similarity in food. Essen- tially the same conclusions were reached by Forbes " from a study of 1,221 Illinois fishes. VARI.\TION IN FOOD OF FISHES COLLECTED IN DIFFERENT LOCALITIES AND AT DIFFERENT TIMES. In order to ascertain how much each species of fish varied in the selection of its principal food at different times and in different places, a study of the data for 1915 presented in section II was made. The chief foods taken at the different stations were summarized as far as possible. If a species took a different kind of food each time it was collected, it will of course be rated as one of versatile food habits; if its chief food was the same in all collections, it is considered as having a limited range of diet. The results of the comparison are shown in Table 5. It will be noted that some species, like the rock bass, bluegill, and black bullhead, are rather versatile feeders; others (Johnny darter, miller's thumb, pickerel, gar) stick to one food. All the species taken together show a change in the chief food with time and place in about half the collections. These estimates, however, do not consider the diversity in size among the fishes examined. VARIATION OF FOOD AT DIFFERENT PERIODS OF THE LIFE CYCLE. The data collected for this paper are not complete enough to make very satisfac- tory comparisons possible between young and adult fish of each species. Of the 32 species studied, in onlj' 20 were enough individuals of different sizes collected so that comparisons can be made. Eight species feed more on amphipods, insect larvae, and adult insects and less on entomostracans as they increase in size. Six change from insect larvae to fishes or crayfishes. Each of the following changes is characteristic of a single species of fishes: Snails and amphipods to plants; oligochsetes to molluscs; Hyalella to fish; insect larvae a Forbes. S. A.: On the food relations of fresh-water fishes: A suxmnary and discussion; pp. 497-504, 1888. FOOD OF THE SHORE FISHES OF CERTAIN WISCONSIN LAKES. 28 1 to earthworms and leeches. Some of the small fishes (Johnny darter, stickleback) show little change. Others which attain larger size (crappie) are versatile and sometimes feed as adults on the same foods used when young. The two fishes which are largely vegetarian when adult (carp, sucker) both make their first food largely from entomos- tracans, then change to insect larvae, and finally to plants. Though the data from which these conclusions are made are by no means full enough to make very definite generalizations, the general course of events is indicated. The most important foods for young fishes are entomostracans, insects and their larvae, and amphipods. Forbes " discussed changes in foods correlated with increase of age fully. V. INFLUENCE OF FOOD ON THE SELECTION OF HABITATS. Shelford (1911a) said "An animal should be associated, first, with breeding condi- tions; second, with the feeding conditions; third, with conditions affording shelter." Of course no species of fish could persist in a body of water that did not have places suitable for breeding. . Most fishes during the breeding season give up feeding more 01 less and become more bold, thus being less protected. If there must be a choice between reproductive activities and something else, reproduction usually comes first. There is considerable variation in the length of time during which breeding activities dominate all others. Many species lay their eggs and take no more care of the young; some even eat their own eggs or young. Other fishes look after the young until they are able to shift for themselves. A cisco finishes its spawning in a few days; the young of the dogfish are watched by the parents for a couple of months. Aside from the actual time spent in breeding, some antecedent activities are doubtless influenced by prepara- tion for reproduction, but in an)' of the fishes discussed in this paper breeding and its associated activities do not occupy more than a fourth of each year, usually much less. Reproductive activities are, then, transitory, but food and shelter are more or less constant necessities. During the greater part of the year the dominant activity of a fish is finding food, and habits of feeding play a considerable part in keeping fishes in particular habitats. Any organism must have a continued supply of materials to furnish substance and energy. If shelter is close to the food supply, so much the better; but if it is not, food must still be sought. According to the data discussed in section II of this paper, the habitat that affords the largest and most varied food supply is the aquatic vegetation along the shore, and it also furnishes good shelter. More species of fishes frequent the shore vegetation than any other habitat, and they together take a greater variety of food than those in any other place. The habitat most favored by fishes next to the general shore vegetation is the weedy mouths of streams; the third choice is sand and pebble beaches; the fourth, rivers and small streams; and the fifth, the little weedy ponds along shore. The number of fishes occurring in different habitats and their chief foods are shown in Table 6. The habitats having the greatest variety of food and shelter have the most species of fishes. If there must be a choice between food and shelter, the former is taken. For example, a pebble and sand beach has less shelter and more available food than a rocky beach».and is visited by five times as many species of fishes. Forbes (1888) has discussed the dependence of the food of fishes on their structural equipment in a mas- o Forbes, S. A.; On Ihe food relations of fresh-water fishes; A summary and discussion, pp. 492-497, 1S88. 282 BULLETIN OP THE BUREAU OP FISHERIES. terly way. It is apparent that structure is of great importance, but behavior must also be considered. If not influenced by other factors, fishes will persistently select certain habitats and foods. The most potent influences in changing foods and feeding habits come with the seasonal cycle and with changes in age. The annual succession of seasons brings breeding, changes in gases and minerals in the water, variations in temperature, fluctuations in food supply and shelter, and other things which require variations in behavior. Young fishes do not have to breed and require different foods from adults. Through all these changing influences, food is in general more important than any other single factor in causing fish to select particular habitats. VI. GENERAL CONSIDERATIONS OF THE FOODS ON THE SHORE FISHES OF LAKES. The food of the 30 lake fishes reported in this paper shows that most species feed along the shore. Young fishes are found more or less in shallow water everywhere, but most of the adults are more specific in their selection of habitats and for the most part frequent the aquatic vegetation, which furnishes food and shelter. The fishes which are not usually associated with shore vegetation live near the bottom (perch, sucker), on rocky or pebbly shores (miller's thumb, Johnny darter), at the surface (silversides) , or in the open water (cisco). Competition between species for the dififerent kinds of food is usually not very keen. When a particular sort of food is abundant, a number of different fishes may feed upon it, but if it becomes scarce the fishes do not all turn to the same diet for a second choice. This specificity in the selection of food enables different species to live together in the same habitats. It is important in considering fish foods and the feeding of fishes to keep in mind that habits change as age increases. Forbes (1888) said, "One-celled organisms and Entomostraca are the natural, and practically the only, food of an undifferentiated small fish; and to be at liberty to grow, the fish must either change its food (as is usually done) or must develop a special apparatus (commonly a set of fine gill rakers) for the separation of Entomostraca from the waters in which they s\vim. A few apparently become vegetarians at once; most pass into or through an insectivorous stage. After this a few become nearly omnivorous, like the bullheads; others learn to depend chiefly on molluscan food — the sheepshead and the redhorse species — but many become essen- tially carnivorous." The great dependence of many species of young fishes on ento- mostracans makes them rivals to some extent for the same foods, but, as Forbes pointed out, this is offset in part by the seasonal differences in the time of hatching. Some fishes also begin to eat small dipterous larvae as soon as they are able to feed. From the data presented in this paper it appears that insect larvje are of as much importance for young fishes as entomostracans. Adult fishes fall readily into classes, according to their chief foods — vegetarians, piscivores, insectivores, those that eat entomostracans, and those that feed on mud and sediment. The chief vegetarians in Wisconsin lakes are the carp and sucker. It is an axiom in biology that, in any particular part of the earth, the vegetarians must greatly exceed in numbers the carnivorous animals which feed upon them, and in general this law is fulfilled among the fishes. The insectivorous fishes (basses, darters, etc.) usually secure their food when it is in the lar\'al condition, and, in lakes, adult FOOD OF THE SHORE FISHES OF CERTAIN WISCONSIN LAKES. 283 insects are of much less importance than immature stages. The fishes feeding on ento- mostraca (cisco, bream, crappie, perch, carp, etc.) are partly adults and partly young fishes which will later turn more to other foods. In spite of the fact that these little crustaceans are an important element in the food of most young fishes, they do not rival insects. The total amount of insect food (36.3 per cent) in Table i is nearly t\\dce as great as the total amount of entomostracans (19. i per cent). The piscivorous species (pike, gar, pickerel, bowfin) depend on small fishes which get their food from plants directly or indirectly through entomostracans or insect eaters. Scavengers (sucker, blunt-nosed minnow, etc.) get organic remains from the mud and debris at the bottom of the lake or among the aquatic plants. Doubtless, fishes affect each other to a con- siderable extent by eating spawn. The perch in Lake Mendota follow the breeding suckers and ciscoes inshore and eat their eggs. Table i shows that four species eat the spawn of other fishes. Without doubt this number could be increased by more extended examinations during breeding seasons. The nature of the food influences the flavor of fishes, thus enhancing or decreasing their desirability as food for man, and some particular kinds of food seem to make fishes more or less palatable. One of the best food fishes in Wisconsin lakes is the wall-eyed pike, which feeds on fish and frogs. The pickerel is also of good flavor and likewise eats fish, but the bowfin and gar, though they feed mostly on fish, are most undesirable for food. All fishes feeding largely on entomostracans or insects (and which attain suffi- cient size to be eaten) are of good flavor. Feeders on vegetation or mud are in general less desirable than carnivorous or insectivorous species. Little is known concerning the amount and variety of food required by fishes. Putter (1909) did some work along this line, and rations on which certain species thrive have been worked out in hatcheries, but there is no general satisfying knowl- edge concerning the amount of food required, the variety necessary, the value of differ- ent kinds of foods for metabolism, the rate of digestion, the percentage of foods digested, and other matters relating to the value of foods. In its broad relations the matter presented in this paper is preliminary to more important studies which should be made on the food requirements of fishes. The prob- lem for the fish culturist and scientific investigator involves work in a number of differ- ent fields. The food and feeding habits of fishes must be thoroughly known. The work of Forbes and that presented in this paper contribute in this connection to a knowl- edge of the fishes in the United States. Another line of investigation must be in the chemical nature of foods. Studies are now being carried out by the Wisconsin Geological and Natural History Survey in which adequate quantities of different species of aquatic organisms are being analyzed. It will also be necessary to determine many things relating to the general metabolism of fishes — amount of food necessary, kinds of food necessary, rate of digestion and assimilation, what proportion of food eaten is digested, etc. When all these things are known, it will be possible to ascertain definitely why fishes thrive on certain kinds of foods and fail to do so on others. It will also be possible to prescribe proper rations with some confidence. The recent work on the etiology of beri-beri and the illuminating researches of McCollum and Davis (1915) on the causes of growth open up new possibilities. These investigators have made very exact determinations of the substances and amounts necessary for proper rations, and the methods employed may be applied to fishes with profit. 284 BULLETIN OF THE BUREAU OF FISHERIES. But the day when we shall know enough to figure out proper rations is far in the future, and in the meantime every effort should be made to find better foods for growing fishes. There is no reason why we should feed flour and liver forever without knowing why. The recent work of Atkins (1908) in which trout were reared on fly lar\'se is very suggestive and should be extended. There is no reason why other "natural" foods should not be fed to growing fishes in hatcheries. Entomostracans are easily collected in quantities with a pump or tow net. At some hatcheries (Lyell, 1902) they have been collected at intervals and fed to fry with good results. There is no reason why insect larvae, snails, amphipods, earthworms, and other abundant living foods should not be more generally collected or reared as food for j'oung fishes. Table i. — Summary op Fish Foods. [All fifTures concerning food mean percentages by volume. In the "habitat" column the significance of the numbers is as follows: I. aquatic vegetation along shore; 2, sand and pebble beaches; 3, rock beaches; 4, bottom of lake everywhere: s. surface of lake along shore; 6, surface of lake everywhere; 7. open lake; 8. swamp; 9, mouthsof streams; 10. river; 11, small ponds; and 12. small streams. These numbers refer to places where collections were actually made; not to the habitats as indicated by the food. The habitats occurring with the greatest frequency are placed first.] Name. 1 a 1 J3 > < i I t a I &. a .2 4 f 1 a 5 1 1 1 1 1 •a 8 1 57 45 IS SO j6 SO 34 30 42 39 S 5 9 149 149 19 80 80 "S 27 5o 3 66 14 18 55 67. 6 72 9 118. 8 46.3 467.4 30-9 39-6 41.7 293- 4 37-3 47-8 29.3 145-7 40 4 33-3 494-9 51 72- S 66.8 34 99-9 72-9 40 48.8 9P-S 65.6 126. s 103.2 32-7 440 39|-9 3.1 19- I 32 6 24 3 0-3 3-5 ' 14.4 .4 1.4 J- 8 ' 90.1 ■7 S7.I 39-9 7.5 33-6 -4 42.7 21. S 9 19.7 3-2 27.2 IS S-2 17-3 42.2 14-5 1.6 24 4-1 8-1 ..:'.. M 84 4.8 ca .6 •S 2.8 + • 7 + 9-4 .8 1.4 88.8 2!$ 6.1 18. 1 15-3 .6 6.4 1-4 •' 1.3 14.7 8.7 •7 0.9 -9 1-3 0.3 27' 8 3 3-4 3-4 4.0 3 • I 7-1 4-2 u 14.3 19.4 25 4.6 \:l 8 18.7 ' ■ 5 9.1 9»-9 Umbra lima •S •5 I »-S .3 •3 ■9 12.3 •4 17-4 2.8 •3 1-4 I. a o Total number of fishes examined, 1,576: Toad eggs, 0.3; fishes, 13.5; insect larva, 24.8; insect pupse. 6.3; adult insects, s.j hydrachnids, 0.5; large Crustacea, J3.3; Entomostraca, 19.1; MoUusca, 2; OUgochaetes, 3.5; leeches. 0.4; rotifers, 0.2; planU, 4.: debris, etc., 2.6. FOOD OF THE SHORE FISHES OF CERTAIN WISCONSIN LAKES. Table i. — Summary op Fish Foods — Continued. 285 Name. 1 1 13 J3 ■6 1 > < •J u5 .2 S 1 1 •g .■s 1 5 2 S 1 •g 1 a 1 2 5 1 •n •a H > a s < 5" (i •a •c u % -a — ja c" 1 57 45 5° i6 JO 34 3° 42 39 S 5 9 149 loo 149 19 So 8o IIS 27 6o 3 66 14 i8 5S 67-6 72.9 118. 8 46.3 467. 4 30- 9 29-2 39.6 41-7 293- 4 37.3 47-8 29' 3 145-7 40.4 33-3 494.9 SI 72.5 66.8 34 99-9 72.9 40 4S.S 90. S 65.6 126. 5 103.2 32-7 440 39-9 1.4 11.4 1.9 •3 1.6 6.7 16. 5 •3 -7 8-4 57-6 4-3 3-S 33-1 0.4 0.7 16. 1 6.1 3 21.4 3-7 9.4 5- 1 16. 8 .6 7 7-4 14-8 10.4 5-6 3-6 3-6 2-6 18.4 li-S • 7 2.8 3 1.6 59-1 6-9 2-5 48 S8 9 14. 1 6-9 .....^ 3 3-6 25- 8 3-S 3-4 3-2 1-3 15-8 + 19-3 16 3.S 4-9 8.7 IS- 3 32 -4 ' ...... ...... + 14.4 ■4 7-9 16.6 3-4 15- I 33-4 17.6 25.1 4-S 46 •4 .6 2.6 13-9 24-5 6.6 •5 •4 + •3 •4 2.9 '7.8 2.6 2.6 21.6 29.6 + + 3-7 •■ 2 7 6 •3 10.6 5 42 3S-S 10.3 13-6 16.3 5 1-4 1-3 4 7-9 6.1 18.3 6-5 23.1 3-6 1-3 »-3 ■I 2-9 2< X I.I •I 12. 1 3 6 .0.1 =■ + 3-5 Name. II u a >ii 1 1 ■Si; ■^1 < •a s ^ 3 1 1 S7 45 IS 5° i6 50 34 3° 4= 39 5 5 9 149 149 19 8o So "5 37 6o 3 66 14 IS 55 67.6 72.9 118. s 46.3 467.4 30.9 29.2 39-6 41.7 293-4 37.3__ 47-8 29-3 I4S-7 40.4 33-3 494-9 SI 72. 5 66.8 34 99.9 72.9 40 48.8 90.5 65.6 126.5 103.2 32-7 440 39-9 + ... i.o 2.9 2.8 6.4 •9 1.6 •S •9 + 6^3 2-3 + + . 3^ I .8 3-1 3.6 I- 5 :::;:: 0.3 1-3 4-9 I.I + I It _ ' •4 3-7 2.8 42 1.6 + I.I 3-2 21.9 5-5 3-6 ■9 4 0.8 2 + 0.8 + + 12,2 + + 2.9 .6 3-9 .8 3-3 •9 2-3 .8 •7 II. 7 - 7 1-7 19-3 1-3 1-5 6-5 S-7 8.3 1 10 ...... I 2 2.2 9,10 Pcrca tlavcscciis + + + 10 1-3 6,1, 4-7 5-9 13 ■I 3 0.4 ■' •^ 2-5 ...I 1-4 3-8 + - + + + 2 1 2.5! -I FOOD OP THE SHORE FISHES OF CERTAIN WISCONSIN LAKES. 287 Table 2. — Showing Foods Eaten by Seven Species op Fishes Collected Together at Sta- tion 5, August 18, 1915. I •d ei 3 2 ■i '> 2 A .J, 1 ^ 8 £ » R 1 §«' 3 «i 3 '^H 1 .3 1 »> a Name. £ g i •3 J3 •OS s- ^"w 3g S-2 i 1 t ^ S 3 S 1 a" 0.3 n IS u >. 1 1^ '5 24 46.7 30 52-4 124-3 38 24-3 0.7 IS 2-9 25 4 ' 0-3 18.6 5 Pimephales nntatiis 5 ' J 1-3 0.8 0.6 1.9 3 .6 3 ' ' = = ' ■g 3 1 i 3 2 3 Name. Ji J3 1 If U1 >. 1 1 tf) 3 It 1 i 1 3 •0 5 •n a c a .§*" 3 ■s s B ■3 u W 6 ■g S » 7 46.7 2-T 0.8 2 35 SI- 5 0.3 25 30.7 15-5 4 24 124-3 24-3 20. s 3 2-5 ■V r' l-S Number of fish eating ' ' ■ ' ' ' 1 i 3 R . Name. s « 1 .0 1 1 t 3 3 >. 3 43 1 •S u u W A4 23.6 J 30 S2-4 124-3 38 IS j_ 2 3-S 2-S . _ 65 -^ 24 24-3 I J J 2 - 4 s ' • ' ' 3 ' 3 •6 S u 1, S 1 s a.- •3 - •S Name. % % i < .0 -.2 1 fij 1 s 1 •c 1 i 1 1 1 -0 1 i 7 46.7 30 52- 4 124-3 38 0.6 3-4 ..I 0.6 2.1 7-6 Mirrnnteni'! salmnides e 2 Pprra flnvp-^rptit; + Pimenhale<; notatii«; - 82. s ^rhilhpndp*; trvrinin; _ ^ .8 1^ I " ' ' = • ' 2 288 BULLETIN OF THE BUREAU OF FISHERIES. Table 3. — Showtng Foods Eaten by Four Species op Fishes Collected Together at Sta- tion 18, July 3, 1915. Ambloplites nipestris. . Fundulus diaphanus menona. Lepomis mcisor Nolropis heterodon Number of fish ealing 53-6 47-3 45-4 39-9 Ambloplites rupestris. Lepomis incisor Number of fish eating. * > 5 ■8 Ambloplites rupestris Fundulus diaphanus menona. Lepomis incisor Notropis heterodon Niunber of fish eating 53.6 47-3 45-4 39-9 §i Ambloplites rupestris. Lepomis incisor Notropis heterodon. . . . Kitmber of fish eating. . 53-6 45-4 39-9 FOOD OF THE SHORE FISHES OF CERTAIN WISCONSIN LAKES. 289 Table 4. — Showing Foods Eaten by Four Species of Fishes Collected Together at Sta- tion 28, September 17, 1915. ^^ C3 tn ca •0 J3 J3 •3 Name. j2 •a i 2 5 J3 .S2 -s •0 •2£ 3" a 9 •0 •c •a iz; u •a 1 § i g Z < u U Ph di Ph i4 s. ■ -_ J J -^ ^ ' " ^ ■ ' • • J Table 5. — Variation of Foods at Different Places and Times, in Collections Made During 1915- Abramis crysoleucas Ambloplites rupestris. . . , Ameiurus melas Ameiurus nebulosus Amialus calva . . Boleosoma nignun ..... Catostomus commersonii Cottus ictalops Cyprinus carp to Esox lucius Etheostoma flabellare. . . Etheostoma iowae Eucalia inconstans Eupomotis gibbosus Fundulus diaphi nona. Labidesthes sicculus Lepisosteus osseus. . . Lepo: ;me- Micropterus dolomieu. , Micropterus salmoides. Notropis heterodon . Perca flavescens . Percina caprodes ... Pimephales notatus. Pimephales promelas, . . Pomoxis sparoides Roccus chrysops Salmo irideus Salvelinus fontinalis. . . . Schilbeodes g>'rmus ... Schizostediiiin vitreum , Umbra limi Chief items of food eaten. Cladocera (2). Hyalella, Cyclops Crayfish (5) May-fiy uymphs, oUgochjetes, caddis-fly larvee, chiron- omid larvsE (3), chironomid pupie (3). Chironomid larvae, caterpillar snails, oUgochsetes Ostracods, adult insects, amphipods Crayfish, fish remains (2) Chironomid larvae (S), oligocha'tes (3) Chironomid larvae, Ostracods, Cyclops (a) Hyalella (10), Dikerogammarus Chironomid larvae, Ostracods, Hyalella, plant remains Hyalella (2), fish remains Chironomid larvae, Hyalella Hyalella , Chironomid larvte (2), Chydonis, fine debris Toad eggs, Sialis larvae, chironomid larvae. Hyalella, Ceratophyllum . Chironomid larvje (5), amphipods (4), Ostracods (2), oligochaetes, cladocera, fine debris. Chironomid pupa (.5), Cladocera (2), Chironomid adult (2) Fish remains Chironomid larvse (6), amphipods (3), chironomid pupae (2), snails, fine debris, Aphanothece, copepods, cladocera. Insect lar\'£e (2), fish remains, adult insect Adult insects (4), araohipods (r). copepods, cladocera, fish remains. insect larvae, plant remains, crayfish. Chironomid larvae (2). copepods (2), cladocera (2), chironomid pup^, chironomid adult, oligochaetes. filamentous algae. Hyalella (3), cladocerans (3), insect larvce (3). insect adults, fish remains. Chironomid larvee (3), fish eggs Filamentous algas (3). ofigochaetes, chironomid larvae, chironomid adult, cladocerans, fine debris. Chironomid larvae ■ - Fish remains, chironomid pupae, adult insect, Ostracods. daphnia. , Copepods (4), chirnomid larvae, insect adult, fish remains, cladocera Amphipods Chironomid pup^e, amphipods Insect larvEe (2), adult insect, amphipods, cladocera, oligochstes. . . Fish remains (2), fish, and frogs Ostracods (2). amphipods (2), chironomid larvae (2), earthworm, plant remains. Number times col- lected. Number of chief foods. 290 BULLETIN OF THE BUREAU OP FISHERIES. Table 6. — Number of Species of Fishes Found in Diwerent Habitats and the Chief Items of Diet Eaten in Each in 1915. Habitat. Number of spe- cies. Chief items of diet, and number of species eating each. 7 7 3 Dipterous larvae, 5; 6sh, 4; cladocerans. 4; adult Hemiptera, 2: copepods. 2; dipterous pupae, 1; ephemerid nymphs, 1; gastropods, i; amphipods, z; ostracods. i. Dipterous larvae, 4; adult Hemiptera, 2; amphipods, 2; cladocerans. 2; cope- pods. I. Dipterous larvae, 4; cladocerans, 3; ephemerid nymphs, i; adult Hemiptera. i; amphipods, 1; copepods, i. Dipterous larvse, 3; fish, i; adult Hemiptera, i; amphipods. i; cladocerans, i. Dipterous larvce, 2; amphipods. 2; dipterous pupae, i; cladocerans, 1; ostra- cods, I. Dipterous larvje. 2; ostracods, i. Amphipods. 2. Amphipods, i; copepods, i. Cladocerans. 1. Copepods, I. Surface of shore water I BIBLIOGRAPHY. Atkins, C. G. 1908. Foods foryoiing salmonoid fishes. Bulletin, U. S. Bureau Fisheries, vol. xxvin, pp. 839-851. Washington. Baker, F. C. 1916. The relation of mollusks to fish in Oneida Lake. Technical Publication no. 4, N. Y. State College of Forestry, Syracuse University, p. 366. COKER, R. E. 1913. Water conservation, fisheries and food supply. Popular Science Monthly, pp. 87-99. Cole, L. J. 1905. The German carp in the United States. Report, U. S. Commissioner Fisheries (1904"!, pp. 523-641. Washington. Forbes, S. A. 1880. The food of fishes. Acanthopteri. Bulletin, Illinois State Laboratory, Natural History vol. I, p. ig-70. Urbana. 1880a. On the food of young fishes. Ibid., vol. i, p. 71-85. 1880b. Food of the darters. American Naturalist, vol. 14, pp. 697-703. 1883. The food of the smaller fresh-water fishes. Bulletin, Illinois State Laboratory, Natural History, vol. i, pp. 65-94. 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