9-i A REVISION OF THE ASTAl 'IRE. 



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. Blandingu, affirm, and Bariomi. Ra- 

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

 of G.fossor, that it might prove to be C. Diogenes. 



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

 Museum of Comparative Zoology (Cat. No. 3590) there are three second- 

 form males of a Cambarus which closely resemble O. propinquus, but the 

 sexual appendages are longer, as in C. nixf/ras. 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 To mm. long. 

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



39. Cambarus Harrisonii. 



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



Cambarus Earrisottii, Faxon, Proc. Amer. Acad. An- ami Sei., XX. 130, 1S84. 



Male, form I. — Rostrum long, narrow, deilexed, 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; anterolateral margin 

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

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

 hast 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 long, posterior margin rounded, posterior margin of basal segment 

 Idspiiious on each side. Basal segment of antennule with an internal, sub- 

 apical, inferior spine. Antennae as long as the body; second segment armed 

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

 width, widest near the middle, thence tapering to the acute external apical 

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

 cate. Third pair of maxillipeds hairy within. Chelipeds of moderate length, 

 thick; chela large, broad, coarsely punctate above and below, inner margin 



