880 THE AMERICAN NATURALIST. (VoL. XXXIII. 
CC. Natatory setæ of the second antennæ reaching to the 
base, but not to the tips of the terminal claws; claws 
of abdominal rami smooth or feebly denticulate 
Erpetocypris 9 
CCC. Natatory setæ of the second antennæ reaching to or 
slightly beyond the tips of the terminal claws. 
D. Dorsal setæ of caudal rami rudimentary or absent 
and the terminal claws of the abdominal rami 
coarsely denticulate . . . Stenocypris 14 
DD. Dorsal setz of caudal rami normally developed. 
E. Pasthenogenete~ «60 a. Cypris 8 
HE. Seria <<. . Cyprinotus 7 
BBB. Caudal rami exceedingly nae aaa Ae ‘Gatley sete of 
both pairs of antennz well developed, palp and masticatory 
lobe of first maxilla narrow . . . . . .  Cypricercus 5 
1. Candona. Baird, 1850. 
Antenne of female five-jointed, of the male six-jointed. Natatory sete 
absent. Two characteristic sensory sete occur between the fourth and 
fifth joints of the second antenne of the male. Branchial plate of the 
second maxilla composed of two unequal pectinated sete, which are 
attached to the basal portion of the maxilla. The palp of the second 
maxilla of the female is two-jointed and terminates with three pectinated 
bristles; of the male is unjointed and differs in shape from that of the 
female. Second foot either five- or six-jointed, terminating in two unequally 
long, backwardly directed sete and one forwardly directed seta. Caudal 
rami strong, bearing two terminal claws, the dorsal seta of the ramus usually 
quite remote from the claws. At the origin of the rami the dorsum of the 
body terminates in a short seta. Eye small. Males usually more common 
and larger than the females. Seven rows of chitinous spines arranged 
around the central cylinder of Zenker’s organ. Cannot swim, but creeps 
along the bottom, or burrows in the mud or sand. 
a. One of the shorter sete of the tip of the ees foot sharply 
reflexed . reflexa Sharpe 
aa. Sete at the tip of the second fooi not cited: 
b. Length of shell about 1.50 mm., shell inequivalve, second foot 
six-jointed . : . . C. crogmani Turner 
bb. Length of shell between 0.90 mm. sid 1.25 mm. 
‘¢. Caudal rami curved, second foot six-jointed. 
d. Terminal claws of caudal rami stout 
abeformis Fischer 
dd. Terminal claws of the caudal rami Maas, spines on the 
first mandibular process of first maxilla not toothed. 
