CAMBAEUS. 47 



rounded in front, twice as wide as long; third maxillipeds hairy on inner and lower 

 aspects ; chelte 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. E. 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 aud 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. in'opinquus — and the non-tuberculated annulus 

 of female. 



" Found by Dr. P. E. Hoy on the shores of Lake Michigan [at Eacine, Wis.], having 

 been washed ashore during a storm." — Bundy, Geol. Wis., Vol. I. p. 402. 



Color, " dark cream, darker along the sxitures." 



This species is known to me only through the descriptions of Bundy. In his earlier 

 description, in the Bulletin of tlie Illinois Museum of Natural History, be states that the 

 rostrum has " small teeth near apex," and that the carinse 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 Bandy's description, 

 which undoubtedly means inner margin of outer finger hairy. 



GROUP II. (Type C. advena.) 



Third segment of third puir of legs of nude hoolced. First pair of (didominal legs 

 of male similar to those of Group I. 



The species of this group seem to form tlie passage from Group I. to 

 Group III. (C. Bartonii). 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. simnlans, C. 3fexicanus, and C. Citbemis resemble in 

 their general form and shape of chela the species included in Group I. The 

 chela and antennal scale of C. simnlans are much as in C Blandingii, var. 

 acida. In 0. Mexicanus and C. Cubensis the chela is sub-cylindrical and 

 slender, and covered with small ciliated squamous tubercles. C. advena, 



