North AmeTican Fresh-icater Ostracoda. 461 



Cypria pustulosa n. sp. (PI. XL VIII., Fig. 6-10.) 



This species is .51 ram. long, .39 mm. high at the 

 highest part, and .22 mm. wide; clear brownish in 

 color, with a dark patch anteriorly, another just above 

 and posterior to the eye-spot, and still another on the 

 posterior part. Both extremities are hairy, the disc 

 moderately so. Lucid spots (Fig. 6) six, four large and 

 two small, the smaller ones situated ventrally. All are 

 elongate and situated near the center of the shell. 



Seen frorii the side (Fig. 7), the whole specimen seems 

 to be highly arched, owing to the presence of a dorsal 

 flange on the left valve, which is otherwise of the form 

 of the right. Right valve (Fig. 6) regularly arched 

 dorsally; both extremities fully rounded, the anterior 

 sloping, however, somewhat more rapidly ; ventral mar- 

 gin nearly straight, except a small sinuation at the middle. 

 Anterior margin of right valve (Fig. 6) with a row of 

 thirteen to sixteen small tubercles, and just pos- 

 terior to the ventral sinuation are three or four others, 

 which are not so conical but seemingly flattened out 

 and pointed posteriorly. 



The sense club on the third segment of the second an- 

 tennae reaches but to the upper quarter of the segment, 

 the terminal part being bent outwardly; natatory setse 

 three times as long as the distance between their place 

 of insertion and the tip of the claws; terminal segment 

 twice as long as broad. 



Palp of first maxilla very prominently developed, the 

 first segment twice as long as broad, the terminal seg- 

 ment nearly circular, with two well-developed setss and 

 three or four shorter ones. 



Terminal claw^ of first pair of feet (Fig. 8) smooth and 

 as long as the two segments preceding the last; the 

 segment preceding these two hairy. 



Terminal segment of second foot (Fig. 10) small, cai-ry- 

 ing two equal, simple, distally directed setae and a re- 

 flexed one, which is as l6ng as the last three f-fgrnents; 

 penultimate segment provided with a row of cilia at its 



