CAMBARUS. AT 
rounded in front, twice as wide as long; third maxillipeds hairy on inner and lower 
aspects ; chels short, smooth above, serrate on interior margins; fingers short, nearly 
straight, costate and punctate above, contiguous margins tuberculate, exterior one hairy ; 
third joint of third (and fourth ?) thoracic legs of male hooked. (Of three males sent me 
by Dr. P. R. Hoy, not one had the fourth thoracic legs remaining.) 
“ First abdominal of male short, truncate, with three short, obtuse teeth directed out- 
ward from the posterior margin at apex. A smooth groove passes up on the outside of 
the leg between these teeth and the anterior margin. 
“Ventral annulus of female flat, transversely elliptical, posterior margin slightly 
elevated. 
“This species is closely related to C. acutus, but may be at once separated by the 
shorter hands—similar to those of C. propinqwus—and the non-tuberculated annulus 
of female. 
“Found by Dr. P. R. Hoy on the shores of Lake Michigan [at Racine, Wis.], having 
been washed ashore during a storm.” — Bundy, Geol. Wis., Vol. I. p. 402. 
Color, “dark cream, darker along the sutures.” 
This species is known to me only through the descriptions of Bundy. In his earlier 
description, in the Bulletin of the Ilinois Museum of Natural History, he states that the 
rostrum has “small teeth near apex,” and that the carine are “ parallel, separated from base 
of rostrum by slight grooves.” In this description it is said that the “third and fourth 
joints of third thoracic legs” are hooked. This is probably a printer’s error for the “ third 
joint of third (and fourth ?) thoracic legs of male hooked” of the later description. Misled 
by this typographical (?) error, Forbes, in his synopsis of the species mentioned in the 
paper in the Bulletin of the Illinois Museum of Natural History, places this species with 
C. gracilis in the group with hooks only on the third pair of legs. The “outer margin of 
finger hairy,” of Forbes’s diagnosis, seems to show a misconception of Bundy’s description, 
which undoubtedly means inner margin of outer finger hairy. 
GROUP II. (Tyrr C. advena.) 
Third segment of third pair of legs of mate hooked. First pair of abdominal legs 
of male similar to those of Group TL. ; 
The species of this group seem to form the passage from Group I. to 
Group II. (C. Barton). The first pair of abdominal appendages of the male 
are similar to those of the species in the C. Blandingii group, being truncate 
at the tip, the outer part terminating in one or two short tubercles or teeth, 
the inner part in a short, erect spine. Only the third pair of legs of the 
male are hooked. C. simulans, C. Mexicanus, and C. Cubensis resemble in 
their general form and shape of chela the species included in Group I. The 
chela and antennal scale of C. simulans are much as in C. Blandingii, var. 
acuta. In C. Mexicanus and C. Cubensis the chela is sub-cylindrical and 
slender, and covered ‘with small ciliated squamous tubercles. C. advena, 
