DeRyke and Scott 21 



Micropterus salmoides Lacepede (large mouth black bass). 



50 mm. 25 Leuceruthrus micropteri; 8 ephemerida larvae; 1 Hyalella 

 knickerbockeri ; 1 minute piece of fish flesh; 4 Chironomus larvae. 



39 mm. 6 Hyalella; 3 Chironomus larvae; 2 Leuceruthrus micropteri. 



35 mm. 18 Daphnia longispina; 11 Daphnia retrocurva; 4 Bosmina 



longirostris ; 110 copepods. 

 31 mm. 2 Hyalella knickerbockeri; 3 Chironomus larvae; 2 Leuceruthrus 



micropteri; 4 mutilated, partially-digested cladocera; 1 ephemerid 



larva; 5 Cyclops. 



45 mm. 17 Leuceruthrus micropteri. • 



40 mm. 1 Leuceruthrus micropteri, mutilated and partially digested; 



fragments of a small adult insect. 

 Catostomus nigricans Le Sueur (hog-molly). 

 24 mm. 1 may-fly nymph. 

 184 mm. 27 Chironomus larvae; 9 may-fly larvae. 



Collection 27 



August 13, 1920. Potamogeton, Elodea, algae, Vallisneria, Chara, duck- 

 weed, Myriophyllum and Ceratophyllum ; sand; two feet; clear; fair and 

 warm; 11:00 a. m. ; seine. 



Fishes examined in this collection 



Micropterus salmoides Lacepede (large mouth black bass). 

 329 mm. Empty. 

 140 mm. 1 piece of fish flesh 10 mm. x 40 mm. 



46 mm. 1 damsel-fly nymph; 3 Chironomus larvae; 1 Hyalella knicker- 



bockeri and 3 cladocera. 

 48 mm. Odonata nymphs; 4 Hyalella knickerbockeri; 3 Chironomus 

 larvae and 2 Ceratopogon. 

 Esox vermiculatus Le Sueur (grass pike). 

 252 mm. Cray-fish cheliped 13 x 40 mm. 

 272 mm. 1 piece of fish flesh 50 mm. x 15 mm. 



Summer 1921 



Collection 28 



June 20, 1921. Chara, Potamogeton, spatter-dock, Elodea, Ceratophyllum; 

 marl and vegetable debris; six feet; clear; clear and hot; 11:30 a. m.; hook 

 and line. 



Fishes examined in this collection 



Lepomis pallidus Mitchill (bluegill). 



113 mm. Very small fragments of animal tissue unable to determine. 

 83 mm. 1 beetle 5 mm. long. 



Collection, 29 



June 21, 1921. Chara; sand and mud; three feet; clear; clear; 10:00 

 a. m. ; seine. 



