362 CRAYFISHES. 



Two specimens, 1 c?, 1 9 , in the U. S. N. M., No. 20,073, from Piobesi, near 

 Turin, Italy, received from the Turin Zoological Museum agree in the essential 

 characters with the Pompeiian specimens. 



From these specimens I infer that the Cisalpine craj-fishes constitute a 

 marked geographical race, which in some respects (viz. the form of the rostrum, 

 antennal scale, epistoma, and gonopods) shows an approach to Astacus astacus. 

 It is not, however, liable to be confounded with that species, since the median 

 carina of the rostrum is not denticulated, and the post-orbital ridges are entire, 

 not broken up into an anterior and a posterior section as is the case with Astacus 

 astacus. In the important matter of the branchial apparatus, moreover, Astacus 

 pallipcs italicus differs from A. astacus and agrees with A. palKpes in having but 

 two rudimentary pleurobranchiae on each side of the body, upon the eleventh 

 and twelfth body-segments.' 



The craj'fish found in the neighbourhood of Madrid, Spain, is in almost 

 every respect like the typical French Astacus pallipes. It does, however, show 

 an approach to the Italian examples in one regard, viz. an enlargement of the 

 anterior process of the epistoma, and with this in a few specimens goes a tendency 

 toward a broadening of the rostrum. It would ncA'crtheless be an over-refine- 

 ment to separate the Spanish crayfishes from Astacus pallipes. 



Cambarus digueti Bouvier. 



Cambarus digueti Bouv., Bull. Mus. d'Hist. Nat., Paris, 1897, 3, p. 225. 

 Cambarus carinalus Faxon, Proc. U. S. Nat. Mus., Feb. 17, 1898, 20, \i. 648. 



New locality: — Ocotlan, State of Jalisco, Mexico (Field Mus. Nat. Hist.). 



Cambarus pilosimanus Ortmann? 



A young female crayfish, 35 mm. long (M. C. Z., No. 7,405) was collected 

 by Mr. J. L. Peters at Camp Menzel, 36 miles from the mouth of the Hondo 

 River, in the Territory of Quintana Roo, Mexico, March 27, 1912. It is closely 

 affined to C. pilosimanus and C. williamsoni of Ortmann, if not identical with one 

 of these. It presents certain features, however, that are not found in either of 

 Ortmann's species; viz: — there are two well-marked spines, one above the 



' This was dotfrmined by examination of tlie brancliial apparatus of two examples from the type 

 lot of A. p. ilalicus from the River Sarno. The rudimentary gilts borne on the eleventh and twelfth 

 somitts have the form of reduced simple filaments representing the stem of tlie completely formed gill. 



