DeRyke and Scott 17 



Collection 20 



July 12, 1920. Potamogeton, Vallisneria spiralis and Chara; marl; twelve 

 feet; roily; clear; 9:45 a. m. ; hook and line. 



Fishes examined in this collection 



Lepomis pallidus Mitchill (bluegill). 



92 mm. A mass of about 100 fish eggs; 5 nematoda; head and frag- 

 ments of an adult beetle. 



96 mm. 8 fish eggs; 3 water mites; 3 Chironomus larvae; 6 ostracods; 



2 small pieces of Potamogeton 20 mm. long by 2 mm. wide; grains of 

 sand; half-digested insect tissue. 

 102 mm. 6 snails 1 mm. in diameter; 1 Chironomus larvae, and several 

 heads of Chironomus larvae; about 5 cmm. of plant tissue, apparently 

 Potamogeton. 



97 mm. A mass of about 200 fish eggs. 



Collection 21 



July 14, 1920. Chara, Potamogeton, Vallisneria spiralis, Myriophyllum; 

 marl; twelve feet; roily; clear; 10:30 a. m. ; hook and line. 



Fishes examined in this collection 



Perca flavescens Mitchill (yellow perch). 



112 mm. 3 Chironomus larvae; 2 odonata nymphs; 8 snails. 



95 mm. 1 snail; Amnicola limnosa, variety porata; Goniobasis. 



78 mm. 6 fish eggs. 



88 mm. 4 cladocera and 2 tricoptera cases. 



Collection 22 



July 17, 1920. Myriophyllum, Vallisneria spiralis, Chara, Potamogeton; 

 marl; ten feet; clear; clear; 10:30 a. m.; hook and line. 



Fishes examined in this collection 



Perca flavescens Mitchill (yellow perch). 



100 mm. 3 tricoptera; 2 cmm. of plant tissue; a few fragments of tricop- 

 tera larvae. 



113 mm. 3d or 4th walking leg of a large cray-fish; 1 damsel-fly nymph; 



the partially-digested abdomen of a large insect. 

 92 mm. 1 Bosmina; 1 cladocera; macerated neuropteron or dipteron. 

 118 mm. 1 odonatid nymph. 



114 mm. Empty. 



115 mm. Empty. 



110 mm. 1 small fish 25 mm. long; 5 cmm. of fish flesh; 1 odonatid nymph; 

 5 snails 2 mm. in diameter. 

 Lepomis pallidus Mitchill (bluegill). 



82 mm. 1 adult tricopteron; 1 tricopteron case; 1 very small snail. 



98 mm. 5 cmm. of Potamogeton plant tissue. 

 Micropterus salmoides Lacepede (large mouth black bass). 



180 mm. Fish (Labidesthes sicculus Cope) 80 mm., 70 mm., 78 mm., and 



