38 A REVISION OF THE ASTACIDAL. 
cillatus 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, 25mm. Abdomen, 26 mm. 
Rostrum, 5mm. From tip of rostrum to cervical groove, 16.5 mm. Car- 
diac region, 8.5mm, Width of areola, .6 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 (©. 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 
Zodlogy any more precisely indicated. 
14, Cambarus Wiegmanni. 
Astacus (Cambarus) Wiegmanni, Wxtcuson, Arch. f. Naturgesch., XII. Jahrg., I. 99, 1846. 
? Cambarus Wiegmanni, Hacen, Ill. Cat. Mus. Comp. Zool., No. TI. p. 54, Pl. III. fig. 151, 1870. 
Cambarus Wiegmanni, Faxon, Proc. Amer. Acad. Arts and Sei., XX. 138, 1884. 
Four species of Cambarus have been described from Mexico; viz. C. Wieg- 
manu Krichs., C. Mexieanus Erichs. C. Aztecus Saussure, and C. Montezume 
Saussure. C. Wiegmann’ has hooks near the base of the third and fourth pairs 
of legs of male, tuberculated chele, carpus dentated on the inner border. 
C. Mexicanus has only the third pair of legs of the male hooked, chele 
granulated, carpus unarmed. C. Aztecus also has the third pair of legs 
hooked in the male, chelz granulated, more compressed than in CO. Mexi- 
camus, carpus armed with some spines within and below. It is doubtful 
whether this be specifically distinct from OC. Mexicanus. In C. Montezuma 
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. anmunis, 
collected at Orizaba by Prof. Sumichrast. An undescribed Parastacine occurs 
at Colima, on the west coast. 
The types of Erichson’s two Mexican species of Cambarus, C. Wiegmann 
and C. Mexicanus, could not be found in the Berlin Museum, either by Hagen, 
who examined the collection in September, 1870, or by Von Martens (Arch. 
T 7 yc ¢ 7° * P 1 ) 
Naturgesch., 1872, p. 131). ©. Wiegmanni alone of the known Mexican spe- 
