262 BULLETIN OF THE BUREAU OF FISHERIES. 



Station 5; June i; number examined, 10. Length: Maximum, 49; minimum, 30; average, 38. 

 Fcx)d: Beetle larvae, 6; May -fly nymphs, i; Helea larvae, i; Chironomusdecorus larvae, 2.7; C. lob if eras 

 larvae, 4.8; Orthocladius sordidellus larvse, 37.7; Probezzla glaber larvae, 0.4; C. digitatus pupse, o.i; 

 Hyalella, 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; amphipods, 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 larvae, 1.2; Orthocladius 

 sordidellus larvae, 0.5; Prob-zzia glaber larva, 2; Ecdyurus maculipennis nymphs, 16.8; Orthocladius 

 sordidellus pupae, c!- Tanypus monilis pupae, 0.1; C. decorus pupae, 0.5; C. digitatus pupa, i; Corixa 

 adults, 0.4; Hyalella, 30.1; ostracods, 7.9; Cyclops, 2.2; Chydorus sphaericus, 7.9; Pleuroxus pro- 

 curvatus, 0.2; Planorbis, 14.4; Physa, 5.8; oligochsetes, 2.5; fine debris, 5. 



Summary. — Food: Insect larvae, 21.4; pupae, 1.8; adult insects, 0.4; amphipods, 30.1; ostracods, 

 7.9; copepods, 2.2; cladocerans, 8.1; snails, 20.2; oligochsetes, 2.5; fine d6bris, 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 larvae, 1.4; Chironomus plumosus larvae, 

 2.1; Tanypus monilis larvae, 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 

 pupse, 0.4; Chironomus digitatus pupae, 0.2; Hyalella, 11. 4; ostracods, 0.3; Cyclops, 0.1; Chydorus, i; 

 fine debris, 26. 



Summary. — 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; cl^ironomid larvae, 3; Chironomus lobiferus larvae, 3.6; C. abbreviatus larvae, 

 0.2; Probezzia glaber larvae, 0.5; Protenthesculiciformis 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, +. 



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; Eurycer- 

 cus, 8.3; oligochaetes, 6.3. 



Summary. — Food: Inject larvae, 30.8; amphipods, 40; ostracods, 5; copepods, 1.3; cladocerans, 14.9; 

 oligochaetes, 6.3. 



Grand summary for IQ14 and iQi;. — Number examined, 149. Length: Maximum, 67.5; minimum, 

 25.4; average, 40.4. Food: Fish embryos, 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; Sphseridae, 0.4; 

 snails, 3.5; oligochaetes, 2; nematodes, +; 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 Chydoridae and the species of insect larvae found in the present 

 investigation indicate that the top minnow frequently feeds near the bottom or among vegetation. 



Labidesthes sicctdus (Cope). Brook silverside. 



Datafor igi4 (Pearse, 1915). — Number examined, 50. Length: Maximum, 47.9; minimum, 15.4; 

 average, 3S-7- Food; Insect larvas, 5.1; pupae and adult insect, 42.4; mites, 0.1; ostracods, +; copepods, 

 8.1; cladocerans, 27.3; rotifers, +; protozoans, +; plant remains, 2.5; algae, 8; siltand dfebriSj 3.3. 



Station 23; August 11, 1915; 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 larvae, 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, 3.3. 



Summary. — Food: Insect eggs, 9.5; insect larvae, 5; adult insects, 11. 5; ostracods, 0.3; cladocerans, 

 48.9. 



