CAMBAEUS. 37 



of Hagen's Monograph, figs. 93, 94. This is doubtless Le Conte's species. 

 It is peculiar in having tufts of long hair-like setse on the inner margin of 

 the hand. The only other species known to have these hair-like growths 

 is Astacus Gambelii, from the Western United Stall's, which lias the pilosity 

 on the outer as well as the inner margin of the hand. 



Length, 42 mm. Carapace, 21 mm. Abdomen, 22 mm. From tip of ros- 

 trum to cervical groove, 14 mm. Cardiac region, 7 mm. Width of areola, 

 1 mm. Length of chela, 14 mm. ; breadth of do., 5 mm. 



Of the other specimens referred to C. penicillatus, two young females from 

 Charleston. S. C. (Cat, No. 204) are surely ('. troglodytes. Two other females 

 and two males, form II., also from Charleston (Cat. No. 250), may be the 

 female and second form of the male of C. penicillatus, as claimed by Hagen, 

 but I suspect that they belong to another species. The form of the first pair 

 of abdominal appendages of the male (Hagen, PI. I. figs. 95, 96) is not what 

 one would expect in the second form of C. penicillatus. The antennal scale 

 is narrower, longer, diminishing more rapidly in width beyond the middle. 

 The lack of beard on the hands, a more gradually tapering rostrum with 

 longer acumen, and the trispinous basal segment of the telson also serve 

 to distinguish these specimens from the first form male from Georgia. 



In the collection of Butler University, Irvington, Ind., is a male, form 

 II., collected in Eastern Mississippi by 0. P. Hay, which closely resembles 

 the specimen of C. penicillatus from Georgia, excepting in the following par- 

 ticulars. The base of the rostrum is more clearly foveolate. The areola is 

 only one half the width of that of C. penicillatus, being reduced to such an 

 extent as to admit but one line of impressed dots within its area, while in 

 the Georgian specimen there are two or three parallel longitudinal rows 

 in the narrowest part of the areola. The fore border of the carapace is 

 nm angulated behind the antenna-, as in the specimens from Georgia and 

 Charleston. The seta? that grow from the squamous tubercles on the inner 

 edge of the hand are longer than on the other parts, but are not drawn 

 out into pencils, as in the first form from Georgia. 



The fust pair of abdominal appendages are articulated at the base, re- 

 curved at their distal end. though not so strongly as in the first form from 

 Georgia; internal part with a short apical tooth directed obliquely outwards, 

 external part with two stout apical teeth. The short apical tooth of the 

 internal part of the appendage gives it a. very different appearance from the 

 second form males from Charleston, described above, and referred to C. pern- 



