8i8 



FRESH-WATER BIOLOGY 



70 (71) Shell thin, and dirty to ocherous yellow. 



Cypris (Cypris) iestudinaria Sharpe 1897, 



Length i.is mm., height 0.7s mm., 

 width 0.6s mm. Natatory setae just reach 

 tips of terminal claws. Terminal claw of 

 first leg one-sixth longer than the last three 

 segments. Terminal claw of second leg 

 one-third as long as terminal segment. 

 Furca slightly curved, its dorsal edge ser- 

 rate two-thirds its length, and sixteen to 

 eighteen times as long as wide. Dorsal 

 seta two-thirds as long as terminal one, 

 and width of ramus from subterminal claw. 

 Terminal seta fully one-half as long as the 

 terminal claw. Ejaculatory duct five times 

 as long as wide, with spines thickly set over 

 the entire surface (Fig. 1277 c), instead of in 

 wreaths, as is common. Ponds in woods. 

 Illinois. 



Fig. 1277. 

 Cypris (Cypris) Iestudinaria. (o) Furca; (6) First leg; 

 (c) Part of ejaculatory duct of male, and origin of 

 vas deferens. 



71 (70) Shell dark green to chestnut brown with transverse lighter patches dor- 

 solaterally (Fig. 1278 a-h). 



Cypris {Cypris) fuscata Jurine 1820. 



Length 1.30 mm., height 0.80 to 0.95 mm., width 

 0.80 to 0.8s mm. Right shell overlaps left. 

 Sparsely hairy. Terminal claws of first leg less 

 than one-third longer than the last three segments. 

 Furca weakly S-shaped to nearly straight, and 

 from eighteen to twenty times as long as wide. 

 Terminal seta of furca weak, not more than one- 

 third as long as terminal claw; dorsal seta less than 

 width of furca from subterminal claw and about 

 one-half as long as the terminal seta. Sexual. 

 Common everywhere in shallow, grassy ponds and 

 swamps; April to June. 



Fig. 1278. 

 Cypris (Cypris) fuscata. (a) Variety major, dorsal view, 

 X 20; (5) Variety minor, dorsal view; (c) Side view 

 variety major; (i) Furca, X 125. 



72 Shell dark green with two light patches in region of the eyes (Fig. 

 12790) Cypris {Cypris) reticulata Za.d.da.ch. i&^. 



Length i.io to 1.30 mm., height 0.72 mm., width 

 0.6s mm. Shell usually reticulate or tesselated. 

 Somewhat superficially resembling Cypris fuscata 

 major. Natatory setae reach slightly beyond the 

 terminal claws. Furca straight, weakly bent near the 

 end, and from ten to twelve times as long as wide, and 

 ■faintly toothed along the dorsal margin. Terminal 

 seta slender and of the same length as the dorsal one, 

 which is situated about width of furca from subter- 

 minal claw. Abundant in small, temporary grassy 

 pools. Illinois, Massachusetts, New York, New 

 Jersey. 



Fig. 1279. 

 (0) Dorsal view, X 27J! (i) Furca, X 132J. 



Cypris (Cypris) reticulata. 



