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 larvje, i.i; chironomid larvae, 7.1; Chironomus tentans, 8.g; psychodid larvse, 

 0.3; Tanytarsus exiguus larvae, 6.4; Orthocladius sp. larvae, 0.5; O. nivoriundus larvae, 0.8; Cricotopus, 

 exilis larvae, i.g; C. trifasciatus larvae, 5; C. trifasciatus pupae, 11. 4; Chironomus tentans pupse, 17.3; 

 C. fulviventris pupae, +; Aedes adults, i; leaf hopper, i; ostracods, 2.5; Cyclops, 4.8; Canthocamptus, 

 1.5; nauplii, o.i; Chydorus sphaericus, 20; Ceriodaphnia, o.g; 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 larvae, 0.2; Chironomus fulviventris larvae, 64.6; Tanytarsus exiguus larvae, 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 larvae, 2.5; Tanytarsus exignus larvae, 6.2; Tany- 

 tarsus monilis larvae, 28.2; adult midge, 1.2; Hermannia bistriata, 11. 2; ostracods, 13.7; Cyclops, 22.5; 

 Ceriodaphnia, 1.2; oligochaetes, 7.2; rotifers, 4.7; diatoms, i; gelatinous algae, 1.2. 



Summary. — Food: Chironomid larvae, 36.9; midge, 1.2; terrestrial mite, 11. 2; ostracods, 13.7; cope- 

 pods, 22.5; cladocerans, 1.2; oligochaetes, 7.2; rotifers, 4.7; algae, 2.2. 



Grand summary for IQI4 and 1915. — Number examined, no. Length: Maximum, 51; minimum 

 9.4; average, 29.3. Food: Fish eggs, 0.2; dipterous larvae, 21.5; hemipterous larvae, -f; May-fly larvae, 

 0.6; caddis-fly larvae, o.g; chironomid pupae, 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; Sphaeridae, 0.1; oligochaetes, i.i; rotifers, i.i; nematodes, -1-; algse, 

 1.2; plants, 3.2; silt and debris, 3.7. 



The brook stickleback ate over 41 per cent insects (larvae, 23 ; pupae, 9.1 ; adults, 9) and 38.5 per cent 

 entomostracans. Forbes and Richardson (1908) examined five fish and found about equal parts of plant 

 and animal food— filamentous algae, insects, chironomid larvae, and entomostracans. 



Eupomotis gibbosus Linnaeus. Pumpkinseed. 



Station 17; April 10, 1915; number examined, 3. Lengths: 155, 148, 145. Food: Protenthes, 

 choreus larvae, 0.6; Chironomus fulviventris larvae, 0.6; Enallagma hageni nymphs, 2.6; Sialis larvae, 

 1.6; Colymbetis adults, 20; leeches, 8.3; Planorbis, 40; plant remains, 22.6; fine d6bris, 3.3. 



Station 17; April 13; number examined, 2. Lengths: 133, 126. Food: Toad eggs, 42.5; Planor- 

 bis, 30; plant remains, 5; algae, 15; fine debris, 7.5. 



Station 28; August 19; number examined, i. Length: 116. Food : Chironomus lobiferus larvae, 15; 

 Chrysops larvae, i; Chironomus lobiferus pupae, 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 larvae, 2.5; Stratyiomyia 

 discalis larvae, 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 larvae, 

 35; Leptocella uwarowii adult, 10; Hyalella, 5; crajrfish, 12; Valvata tricarinata, 10; Amnicola limosa, 

 10; Ancylus, 3; plant remains, 5; Vallisneria, 10; Myriophyllum, 2; filamentous algae, 3. 



Grand summary . — Number examined, 9. Length: Maximum, 187; minimum, 116; average, 145.7. 

 Food: Toad? eggs, 9.4; insect larvae, 11. 6; insect pupae, 0.9; adult insects, 9.3; amphipods, g; cray- 

 fish, 1.3; leeches, 2.8; snails, 25.8; sponge, 2.2; plants, 21. g; algae, 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 other things. Forbes and Richardson (igo8) foimd 

 that more than half the food of the fish they examined was molluscs; the rest was amphipods, isopods, 

 and insects. Hankinson (igo8) reported midge larvae, May-fly nymphs, crayfishes, amphipods, snails, 

 leeches, and caddis-fly larvae. Reighard (igis) found snails, insect larvae, and Chara. Insects formed 

 the chief food of those fish examined by Baker (1916). 



