38 A REVISION OF THE ASTACHXE. 



cillutus by Hagen, and the two can hardly belong to the same species. The 

 teeth at the tip of the external part are also shorter and blunter in the 

 Mississippi specimen than in those from Charleston. The hooks on the third 

 and fourth pairs of thoracic legs are very small, mere tooth-like processes. 

 The antennal scale is broad at the tip, as in the Georgia specimen. 



Measurements. Length, 50 mm. Carapace, 25 mm. Abdomen, 26 mm. 

 Rostrum, 5 mm. From tip of rostrum to cervical groove, 16.5 mm. Car- 

 diac region, 8.5 mm. Width of areola, .5 mm. Length of chela, 14 mm. ; 

 breadth of chela, 5 mm. 



This specimen, as well as those from Charleston, may belong to different 

 species from C. penicillatiis, but my material is not sufficient to warrant the 

 establishment of new species. 



Le Conte does not specify from what part of Georgia his specimens came, 

 nor is the locality of the Georgia specimens in the Museum of Comparative 

 Zoology any more precisely indicated. 



14. Cambarus Wiegmanni. 



Asians (Cambarux) Wieymaitni, EKICIISON, Arcli. f. Naturgesch., XII. Jahn*., I. 99, 1846. 



? Cambafiix iriri/mitiiiii, HAGEN, 111. Cat. Mus. Comp. Zodl., No. III. p. 54, PI. III. fig. 151, 1870. 



Cambantx in,-i/matiui, FAXON, Proc. Amer. Acad. Arts aud Sci., XX. 138, 1884. 



Four species of Cambarus have been described from Mexico; viz. C. W/'eg- 

 iiiitnni Erichs., C. Mmcnuns Erichs., C. Aziccus Saussure, and C. Montczvnuc 

 Suussure. (!. Win/iinniitl has hooks near the base of the third and fourth pairs 

 of legs of male, tuberculated chelae, carpus dentated on the inner border. 

 C. Mcximitus has only the third pair of legs of the male hooked, chela) 

 granulated, carpus unarmed. C. Aztccus also has the third pair of legs 

 hooked in the male, chelae granulated, more compressed than in C. Mc.d- 

 rt/HHx, car]) us armed with some spines within and below. It is doubtful 

 whether this be specifically distinct from C. Mcxicanm. In C. Monicziumr 

 the second and third pair of legs of the male are hooked, the carpus and 

 chela- smooth. To the list of Mexican Cambari is to be added C. imnnnii*, 

 collected at Omaha by Prof. Sumichrast. An undescribed Parastacine occurs 

 at Colima, on the west roast. 



The lypes of Kriehson's two Mexican species of Cambarus, C. Wicgwuui! 

 and C. j\l,.,-;<;nii<x. could not be found in the Berlin Museum, either by Hagen, 

 vim examined the collection in September, 1870, or by Yon Martens (Arch. 

 STaturgesch., IS7U. [.. l:;i,. c. Wiegmanni alone of the known Mexican spe- 



