94 A KEY1S10X OF THE ASTACID.E. 



Neither of these- forms has been reported from Pennsylvania or Virginia. 

 The only .species known to me to be common to the three States of New 

 York. Pennsylvania, and Virginia are C. Bkmdhiyii, affuris, and Burtoiiii. Ka- 

 finesque's description fits none of them. Girard surmised, from the habits 

 of C.fossi\ that it might prove to be C. Dioyi'iie*. 



In the collections of the Boston Society of Natural History and the 

 Museum of Comparative Zoology (Cat. No. o590) there are three second- 

 form males of a Cambarus which closely resemble C. p/-<ij/in/jiitis, but the 

 sexual appendages are longer, as in C. rusHcm. The epistoma is long. The 

 carpus has a strong internal median carpal spine and a small basal internal 

 spine ; beneath, the carpus is unarmed. The biserial spines of the meros 

 are well developed. The outer ramus of the first abdominal appendages is 

 a little recurved at the tip. The largest of these specimens is 75 mm. long. 

 No locality is given. They seem to belong to an undescribed species. 



39. Cambarus Harrisonii. 



Plate III. fig. 1, Plate IX. figs. 9, 9'. 



x Iliiffhuiiii, FAXON, Proc. Amcr. Acad. Arts and Sei., XX. 130, 1SS4. 



Male, form I. Rostrum long, narrow, deflexed, excavated ; margins 



thickened, a little convergent; acumen of moderate length, triangular, 



acute; marginal spines short, obtuse, often obsolescent. Carapace flattened 



above, coarsely punctate, granulate on the sides ; post-orbital ridges prom- 



inent, sulcate without, with acute anterior spine; antero-lateral margin 



notched at base of antenna ; cervical suture not sinuate, interrupted on the 



side; lateral spine small, acute; branchiostegian spine obsolete; areola at 



least one half as long as the distance from the tip of the rostrum to the 



cervical groove, of moderate width, punctate, the dots tending to a biserial 



arrangement in the middle portion. Abdomen as long as the cephalothorax ; 



telson lung, posterior margin rounded, posterior margin of basal segment 



bispinous on each side. lia.sil segment of antennule with an internal, sub- 



spiral. inlmnr spine. Antenna- as long as the body; second segment armed 



with a short, acute, external spine: scale as long as the rostrum, of moderate 



i'lili. widesl near the middle, thence tapering to the acute external apical 



Anterior process of epistoma with convex sides, apex blunt or trun- 



riiinl pair ol' maxillipeds hairy within. Chelipeds of moderate length, 



. '""'"I- coarsely punetate above and below, inner margin 



