366 MEMOIRS OF THE CARNEGIE MUSEUM 



I possess five specimens (obtained b_y excliange from (Jberlin Ojllege) from (ine 

 of the two localities oi'iginall_y mentioned by Faxon for this form (Oljerlin, (Jhio), 

 which agree well with his account, with tlie exception that the pubescence of the 

 hands is not developed; there are, indeed, a number of short hairs in some, chiefly 

 the younger, specimens, implanted in the pinictures, l)ut such are also very fre- 

 quently present in (J. prupinqaus (as well as in C. obncuras). These hairs are gener- 

 ally present in ncAV, recently moulted specimens, but wear off with age. 



The male copulatory organs are very similar in shape to Faxon's figure, although 

 they vary slightly with reference to the length of the separated tips. In this 

 respect, however, the variety is closer to the typical form tlian to ('. ohscurua. In 

 addition, I notice in the two males of the first form of this set that the inner part of 

 the male organs, although it tapers to a point on a side view, is different on a poste- 

 rior view. From behind it is]^broadly and bluntly rounded off, a fact which is due 

 to a marked compi'ession and flattening in an anteroposterior direction toward the 

 tip. This is also the case in the male of the second form at hand. Here both tips 

 of the sexual organs are blunt, that of the inner part less so than that of the outer. 

 I cannot see that the tips of the male organs, either in the first or in the second form, 

 are closer together than in C. propi)iquus. 



The armature of the chelipeds in these specimens is slightly different from that 

 of the typical (J. j>rojnnqiit(s, although similar variations have been observed in the 

 latter. In all five specimens there are two distinct spines on the lower side of the 

 carpopodite, one at the articulation with the hand, the other on the anterior margin. 

 The inner margin of the carpopodite, besides the one strong spine, has a distal and 

 a proximal tubercle, and in the two largest individuals (male and female) there are 

 a few additional tubercles on the upper surface (jf the carpopodite. The inner Icjwer 

 margin of the meropodite invariably has in these specimens behind the distal 

 spine a row of small teeth, becoming spiniform in the larger individuals. The num- 

 ber of teeth in this row is from six to eight. In two specimens the outer lower margin 

 possesses a small tubercle behind the distal spine of each cheliped. In one specimen 

 there is only a tubercle on the right side, and two others have only the distal spine. 



In addition to the above specimens from Oberlin I have seen among the Oberlin 

 collections other specimens fi'om the state of Ohio, and have myself collected in 

 eastern Ohio and northern West Virginia a number of specimens, which undoubt- 

 edly belong to the same form. The characters are practically the same, and only a 

 few remarks ai'e necessary. 



1. The keel of the rostrum is invariably lacking. There is not a single indi- 

 vidual which shows any trace of it. 



