230 GEOL. AND NAT. HIST. SURVEY OF MINNESOTA. 
the end of the beak, are curved and bear a lateral flagellum. The 
first foot of the female has a sort of hook (branchial sac?). The la- 
brum is armed with teeth on the posterior face of the triangular pro- 
cess. The intestine is very strongly, almost twice, coiled. The lower 
margins of the valves are feebly spined for three-fourths their length, 
and armed with from one to four teeth at the angle. Length 0.8 mm- 
to 1.0 mm. 
Camptocerecus rectirostris Schoedler. 
PLATE LXII, Fies. 1-3. 
Distinguished from the above, which it closely resembles, by the 
form of the head, which is less rounded and directed anteriorly. It 
hardly exceeds half the height of the body, The beak is sharp. I am 
not sure that Weismann’s figures (1. ¢., Plate XI, Figs. 13 and 14) 
really belong to this species, for the drawing of the post-abdomen 
does not agree with that of P. E. Mueller fully. Outline copies of the 
former are given in Plate LXII, Figs. 1 and 2. The male has a hook 
upon the first foot. Not yet recognized in America. 
Camptocercus latirostris Kurz. 
PLATE LXII, Fias. 5-6. 
C. lilljeborgii, P. E. Mueller (?). 
Closely allied to the next, but distinguished by the position of the 
head, which is a little less depressed, and, especially, by the truncate 
beak. The dorsal margin is convex and crested; the lower outline is 
also convex. The claws are toothed more as in C. macrurus than the 
following. The basal spine springs from the claw itself and not from 
the post-abdomen as in the next. Length 0.9 mm. to 1.0 mm. 
Camptocercus lilljeborgii Schoedler. 
PLATE LXII, Fias. 7-8. 
Head depressed, rounded in front; beak divided at the end by the- 
extension of the fornices. The terminal claws are pectinate for their 
entire length, and the basal spine is seated on the end of the post- 
abdomen. This species, in the main, closely resembles C. macrurus, 
* Camptocercus rotundus Herrick. 
The second of the two species found in America is this short, 
strongly carinated form, which is known from a single gathering. It 
differs from all the above species, with which it agrees pretty well in 
shape, by its more compact form; high dorsal keel (which extends the 
entire length of the body); the long antennules, which extend far below 
the beak; and the somewhat pointed beak. The head is much as in 
