CAMBARUS. 27 
a/ 
differs in some respects from any other seen by me. The granules of the 
carapace are larger, the gastric area more heavily punctate, the rostrum is 
longer (14 mm., the whole carapace being 48 mm., while in New Orleans 
specimens the rostrum is only one fourth the length of the carapace), with 
longer acumen and lateral spies, and narrower at the base, than in New 
Orleans specimens, with less converging sides; the arm is more conspicu- 
ously tuberculated along its upper edge. The lateral thoracic spines are 
prominent, as in the San Antonio form. The areola is obliterated in the 
middle, as in specimens from Louisiana and Alabama. 
A dry cephalothorax of a female in the Museum of Comparative Zotlogy 
(No. 3337), referred to C troglodytes by Hagen (pp. 42, 43), seems to belong 
to C. Clark. As dry specimens are easily transposed, and this is the only 
specimen recorded from the North, I believe the locality to be erroneous. 
C. Clarkii is the species commonly on sale in the New Orleans market. 
5. Cambarus troglodytes. 
Astacus troglodytes, Lx Conte, Proc. Acad. Nat. Sci. Phila., VII. 400, 1855. 
Astacus fossurum, Ln Conte, Proc. Acad. Nat. Sci, Phila., VII. 401, 1855. 
Cambarus troglodytes, Hagen, Ill. Cat. Mus. Comp. Zodl., No. IIT. p. 41, Pl. I. figs. 11-14, Pl. IT. fig. 141, 
Pes Heit Forsus, Bull. Il. Mus. Nat. Hist., No. I. pp. 4, 18, 1876. (After Hagen.) 
Cambarus troglodytes, Faxon, Proc. Amer. Acad. Arts and Sci., XX. 136, 1884. 
Known Localities. — Lower Georgia; Richmond Co., Ga. South Carolina : 
Charleston ; Oakley (Coll. U. 8. Nat. Mus.) ; Columbia (Coll. U.S. Nat. Mus.). 
Illinois: Lawn Ridge, Marshall Co. [?). 
This species resembles C. Clurkii very closely, but is readily distinguished 
by the first pair of abdominal legs of the male, and by the rostrum, which 
is nearly plane above, with very slight marginal teeth (often obsolete), and 
shorter acumen. The areola is very narrow, but not obliterated, in the 
middle. 
Two of Le Conte’s types (both males, form I.) are extant, one in the 
Museum of Comparative Zodlogy, and one in the Academy of Natural 
Sciences of Philadelphia. In each of these museums there is also a small 
female type of C. fossarwm of Le Conte, which does not differ essentially 
from C. troglodytes of the same author. It is difficult to see why Le 
Conte separated the two, unless on the ground of a difference in color 
during life. 
