No. 395.] WORTH-AMERICAN INVERTEBRATES. 881 
A Coot unte so . C. acuminata Fischer 
ee. Color greenish niar variegated with blotches 
of brown: . . . . . C. delawarensis Turner 
cc. Caudal rami not curved. 
d. Terminal claws of rami S-shape. C. sigmoides Sharpe 
dd. Terminal claws not eo the longest one-half as long 
asthe ramus. > . C. recticauda Sharpe 
2. Candonopsis Vávra, 1891. 
Second antennz similar to those of Candona. Mandible bears an ex- 
traordinarily long palp. Branchial plate of the second maxilla composed 
of three plumose bristles. Caudal rami slender, usual dorsal seta absent. 
No species of this genus has yet been found in America. 
3. Cyclocypris Brady and Norman, 1889. 
First antenne seven-jointed. Second antenne five-jointed in female, six- 
jointed in male, no olfactory organ on the fourth joint. Natatory sete of 
the second antennz reach far beyond the tips of the terminal claws. Palp 
of both the mandible and first maxilla normally developed. The second 
maxilla bears a branchial palp and a plate. This branchial palp in the 
female is unjointed ; in the male it forms a hooked prehensile organ. Last 
joint of second foot unusually long, being two thirds the length of the fourth 
joint. Zenker’s organ resembles the corresponding organ of Cypria. Vas 
deferens long and convoluted, copulatory organ quadrangular. Males 
numerous. 
a. Front edge of caudal ramus about twice as long as its terminal claw 
JiS M 
aa. Front edge of caudal ramus about two and a half times the length of 
the terminal claw. 
ó. Terminal claws of caudal rami strong and much bent 
C. forbesi Sharpe 
66. Terminal claws of caudal rami slender and not bent 
C. modesta (Herrick) 
aaa. Front edge of caudal ramus about three times the length of the 
terminal claws. Terminal claws strong, nearly straight, weakly 
bent near the tips... 6 oor ke a e C plobosa® Sars 
4. Cypria Zenker, 1854. 
Second antenne of the female five-jointed, of the male six-jointed. 
Distal extremity of the fourth joint of the second antenna bears two 
olfactory seta. Natatory sete of the second antenne extend far beyond 
