CAMBARUS.: 19 
in the genus Astacus, and in its general form agrees with the corresponding 
limb in the other Cambari. Remarks on the relations of this interesting 
species will be found on page 42. 
I am disposed to regard the Cambari of this group as, on the whole, the 
lowest forms in the genus. The slight degree of specialization of the exter- 
nal male appendages, the tendency toward an oval; astacoid form of body, 
the slender claws and generally toothed rostrum, all point to this. That 
the stout-clawed species with toothless rostrum are derived from forms with 
slender chelee and toothed rostra seems probable from the fact that the latter 
characters are commonly found in very young individuals of all species. 
This group corresponds exactly with Group I. of Hagen’s Monograph. 
Section of the carapace belind cervi- ( Epistoma rounded in front: C. Blandingii, C. 
i Hayi, C. fallax.* 
call grooreilous (seep. 18): Epistoma truncate: C. Clarkii, C. troglodytes. 
Rostrum toothed. ce ere bc 
Posterior Section of carapace short 
5 Areola wide: C. spiculifer, C. versutus, C. angus- 
(see p. 18). a Hea ete Cae) ? ca 
Areola narrow: C. Leconfet. 
tatus, C. pubescens. 
Eyes atrophied: C. pellucidus. 
Rostrum toothless. C¢. Wiegmanni, C. penicillatus, C. Alleni. 
i¢ 
1. Cambarus Blandingii. 
Plate VII. figs. 2, 2', 2’, 2a, 2a (first abdominal appendages of male). 
Astacus Blandingii, Haran, Trans. Amer. Philosoph. Soc., III. 464, 1830.—Medical and Physical Re- 
searches, p. 229, fig. 1, 1835. 
Astacus Blandingii, M1tNe Epwarons, Histoire Naturelle des Crustacés, IT. 332, 1837. (After Harlan.) 
Astacus Blandingii, DE Kay, Zoélogy of New York, Part VI. Crustacea, p. 23, 1844. (After Harlan.) 
Astacus (Cambarus) Blandingii, Exrcuson, Arch. f. Naturgesch., Jarg. XIL., I. 98,1846. (After Harlan.) 
? Astacus Blandingii, Le Conte, Proc. Acad. Nat. Sci. Phila, VII. 400, 1855. 
Cambarus Blandiagii, Hacey, Il. Cat. Mus. Comp. Zodl., No. IIL, 43, Pl. L. figs. 63, 64, Pl. IIT. fig. 140, 
1879. 
Cambarus acutus, var. B, HAGEN, op. ctt., p. 36, Pl. ILL. fig. 144, 1870. 
Cambarus acutus, Apport, Amer. Naturalist, VIT. 80, 1873. (Habits.) 
Cambarus acutus (in part), Switu, Rep. U. S. Comm. Fish and Fisheries for 1872 and 18738, p. 637, 1874. 
(After Hagen and Abbott. No description.) 
Cambarus Blandingii, Faxon, Proc. Amér. Acad. Arts and Sci., XX. 135, 1884. 
Known Localities} — New York. New Jersey: Essex Co.; Delaware River 
and tributaries, near Trenton. Maryland: Baltimore Co, (Coll. P. R. Uhler) ; 
* Tn some specimens of G. ful/ax the hinder section of the carapace is a little less than one half the 
distance from the cervical groove to the tip of the rostrum. @. maniculatus (LeC.) is omitted from the 
above table, as I have seen no specimens answering to the deseription of Le Conte. 
+ Localities for which no authority is given in parentheses are represented in the collection of the 
Museum of Comparative Zoology. 
