North American Fresh-water Ostracoda. 449 



6 (4). Caudal rami curved (PI. XLV., Fig. 1); dorsal 

 seta about twice width of ramus from subterminal 

 claw; claws approximately straight or curved, with 

 a hook-like extremity ; terminal claw one third length 

 of ramus; both claws of nearly the same length, 

 rather stout, moderately toothed. 



C. FABJiFOEMis (S. Fischer). 



6 (2, 3). Shorter seta on last segment of second foot 



three to four times as long as last segment. Dorsal 

 seta of ramus situated at two thirds length of seta, or 

 two and a half times width of ramus, from sub- 

 terminal claw; ramus much broadened at base, a 

 fourth as broad as long; terminal seta half as long 

 as dorsal one. C. acuminata (S. Fischer). 



7 (1). Fourth segment of second foot undivided (sec- 



ond foot therefore five-segmented). 



8 (11). One or both claws of ramus more or less 



S-shaped. 



9 (10). Both claws shghtly S-shaped; ramus more than 



twice as long as terminal claw; dorsal seta of ra- 

 mus four times width of ramus from subterminal 

 claw. C. siGMOiDES n. sp. 



10 (9). Only the subterminal claw S-shaped; term- 

 inal claw more than half as long as ramus, scimitar- 

 shaped ; dorsal seta two thirds as long as subter- 

 minal claw. C. siMPSONi n. sp. 



11 (8). Both claws of ramus as usual (with one 

 l)ackward curve) ; ramus stout, curved ; terminal claw 

 half as long as ramus, and five fourths as long as 

 subtei-minal claw ; dorsal seta one and a half times 

 width of ramus from subterminal claw. 



C. REFLEXA n. sp. 



Candona acuminata S. Fischer. (PI. XLIV., Fig. 5-7.) 

 1851. Cypris acuminuta.S. Fischer (2J?, p. 148. PI. IV., F\^. 12-16). 

 1854. Cypris acuminata, Zenker (75, p. 74, PI. II., Fi^'. D). 

 1889. Candona acuminata, Brady <fc Norman (9, p. 104, PI. IX., 



Fig. 9,10; X., Fig. 5, 6). 

 29- 



