THE OSTRACODA 

 51 (50) Inner anterior edge of right shell plain (Fig. 1278 c). 



62 



52 (53) Dorsal seta of furca more than one-half length of subterminal claw 



(Fig. 1270 c) 54 



53 (52) Dorsal seta of furca not more than one-half length of subterminal 



claw (Fig. 1273 c) 58 



54 (55) Left shell larger than the right, and its edges not tuberculate (Fig. 



1270 b) 56 



55 (54) Left shell smaller than the right, and with a row of scattered tubercles 

 along the inner margin (Fig. 1269 b, e). 



Cypris (Cyprinotus) pellucida Sharpe 1897. 



Shell unusually trans- 

 lucent, and covered with 

 a regular arrangement 

 of dotted lines. Length 

 1.20 mm., height 0.75 

 mm. Clear uniform yel- 

 lowish in color. Left 

 shell slightly smaller than 

 the right, with a row of 

 scattered tubercles along 

 the inner margin. Shal- 

 low ponds and pools; 

 April to September. Illi- 

 nois, Washington, Idaho, 

 Mexico. 



FIG. 1269. 



Cypris (Cyprinotus) pellu- 

 cida. (a) Side view, X 

 20; (b) Dorsal view; (c) 

 Lower anterior margin of 

 right shell; (d) Furca; 

 (e) Inner margin of left 

 shell; (/) Markings on 

 shell. 



56 (57) Right-shell margin tuberculate only at anterior and posteroventral 

 margins. Shell about four-sevenths as high as long (Fig. 

 12700). . Cypris (Cyprinotus) incongruens Ramdohr 1808. 



Shell densely pigmented to quite 

 translucent yellowish in alcohol. 

 Smooth. Length i. 40 to i. 70 mm. 

 Left valve overlaps right. Furca 

 curved, about ten times as long as 

 wide. Spines of first maxillary 

 process toothed. Quite common, 

 even in temporary ponds and 

 watering troughs. Florida, Ohio, 

 Pennsylvania. 



FIG. 1270. 



Cypris (Cyprinotus) incongruens. 

 (a) Right shell, X 22*; (b) Dorsal view 

 of female, X 22}; (c) Furca of fe- 

 male, X 55 ; (d) Penis, X too; () 

 Spines of first maxillary process. X 

 190. 



