34 A REVISION OF THE ASTACII'.E. 



wide and the hands broad; C. versutus has the hand covered with small, 

 close-set, squamous tubercles, the sides of the rostrum are subparallel, and 

 the telson commonly tri- or quadrispinose on each side ; in C. spiculifer the 

 hands bear large tubercles much less closely set than in 0. versutus, the 

 rostrum tapers more between the base and the lateral spines, and the tel- 

 son is bispinose on each side. Each of these five species has characteristic 

 male appendages, figured by Hagen and on Plate VIII. of this Revision. 



11. Cambarus versutus. 



Cambarus r, rsulus, Hagen, 111. Cat. Mus. Comp. Zool.. No. III. p. 51, PI. I. figs. 55-58, PI. III. fi?. 150, 

 1870. 



versutus, Faxon, Proc. Amer. Acad. Arts and Sci., XX. 138, 1884. 



Known Localities. — Alabama: neighborhood of Mobile. Florida: Cape 

 Barrancas [Pensacola Bay?]. 



Cambarus versutus resembles ('. spiculifer in the shortness of the carapace 

 behind the cervical groove, the wide areola, and the two spines on each 

 side of the carapace. In addition to the difference in the male appendages 

 (see Hagen's figures), the chelae are covered with small, closely-set squa- 

 mous tubercles, while in ('. spiculifer the chelae have fewer and larger tuber- 

 cles. In C. versutus the hand is sulcated below, along the inner border, and 

 the areola is a little wider. The telson is tri- or quadrispinose in ('. versu- 

 tus, bispinose in ('. spiculifer. The sides of the rostrum converge less between 

 the base and the lateral spines in ('. versutus. 



Measurements of a male, form I. — Length. 73.5 mm. Carapace, 35 mm. 

 Abdomen, 38.5 mm. From tip of rostrum to cervical groove. I'll mm.; from 

 cervical groove to posterior border of carapace, S.5 mm. Length of rostrum. 

 12 mm.; acumen, 5 mm. Breadth of rostrum at base, 5.5 mm.; between 

 lateral spines. 1 mm. Length of chelae, 33 mm.; breadth of do.. 11 mm. 

 Width of areola, 4 mm. 



Three small dry specimens, two males and one female, from Cape Barran- 

 cas. Fla.. differ from the Alabama specimens in that the rostrum tapers a 

 little more and is lightly carinated above in the middle third of the median 

 line. Although none of the specimens are over M) mm. in length, the males 

 are of the first form, with well-developed hooks on the third and fourth pairs 

 of legs. The male appendages agree with those of C. versutus. The telson 

 is tri- or quadrispinose, and the hand is sulcated below, along the inner 

 margin, as in C. versutus. 



