38 A REVISION OF THE ASTACID^. 



cilMus by Hagen, and the two can hardly belong to (he 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. penicillatus, 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. 



Astacus {Cambarus) Wiegmunin, Ericiison, Arch. f. Natui-gescli., XII. Jalirg., I. 99, 184'). 



? Cumtjurus Wiegmunni, Hagen, 111. Cat. Mils. Comp. Zool., No. III. p. 51, PL III. fig. lal, 1870. 



Cambarus TFief/manni, Faxon, Proo. Aiiier. Acad. Arts aud Sci. , XX. 138, 1884. 



Four species of Cambarus have been described from Mexico; viz. C. Wi<(j- 

 manni Erichs., C. Mexicamis Erichs., C. Aztecus Saussure, and C. Afoiitcziiiiiw 

 Saussure. C. Wiegmanni has hooks near the base of the third and fourth pairs 

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

 C. Mexicanm has only the third pair of legs of the male hooked, chelte 

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

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

 camis, carpus armed with some spines within and below. It is doubtful 

 whether this be specifically distinct from C. 3fexicaiws. In C. Ifonlesunuc 

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

 chelae smooth. To the list of Mexican Cambari is to be added C. immvnis, 

 collected at Orizaba by Prof. Sumichrast. An un described Parastacine occurs 

 at Colima, on the west coast. 



The types of Erichson's two Mexican species of Cambarus, C. Wiegnianni 

 and C. 3Iexicaiu(s, could not be found in the Berlin Museum, either by Hagen, 

 who examined the collection in September, 1870, or by Von Martens (Arcli. 

 Naturgesch., 1872, p. 131). C. Wiegmamri alone of the known Mexican spe- 



