MEXICAN, CENTRAL AMERICAN, AND CUBAN CAMBARI 15 



tened and dilated on the inside, with a shoulder on the anterior 

 margin near the tip ; the end of the inner part has a soft tip, 

 and, in addition, in the male of the first form, a horny spine, 

 which is replaced, in the second form, by a blunt tubercle. 



C. cubensis is closely allied to the species williamsoni, pi'lo- 

 simanus, and mexicanus, but differs in the following characters : 



(1) The dilatation of the inner face of the male copulatory 

 organ is much more pronounced ; the tip of the inner part is 

 more pointed, almost setiform, in the male of the first form ; 

 the horny spine is two-pointed. (2) The rostrum has marginal 

 spines ; these are also present in C. williamsoni and filosi- 

 manus, but are absent in C. mexicanus. (3) The carapace has 

 a small lateral spine, which is sometimes absent; this spine is 

 always missing in C. mexicanus, while the other two species 

 have two distinct lateral spines on each side. 



3. Faxon's description of the annulus ventralis of the female 

 (1. c, p. 52) is correct: " composed of a large anterior bilobed 

 tubercle, and a smaller posterior tubercle." I only wish to add 

 that the small posterior tubercle possesses the S-shaped longi- 

 tudinal fissure commonly seen in Cambarus, and it seems to me 

 that only this tubercle ought to be regarded as the annulus. I 

 was able to observe the shape of the annulus only in the largest 

 female of the first set ; in all other females, which are small, it 

 is very indistinct, a fact that has also been noticed by Faxon. 



For the rest, this species has been well described by Faxon, 

 but in the figure of the anterior part of the animal [pi. 2, f /), 

 the marginal spines of the rostrum have been omitted. These 

 spines are small, but present in all specimens at hand. 



V. CAMBARUS (CAMBARUS) WIEGMANNI Erichson. 



Camb. wiegm. Faxon, Mem. Mus. Harvard, X, 1885, 38 (liter- 

 ature). — Hay, Amer. Natural., XXXIII, 1899, 959 anc * 9^4- 



Camb. (Cambarus) wiegm. Ortmann, Proc. Amer. Philos. 

 Soc, XLIV, 1905, 102. 

 Hagen's female type specimen in the Philadelphia Academy 



agrees rather well with a male of the first form present in the 



same collection. This latter one is from the Cope collections 



and represents a new locality for the species : 



