CAMBAEUS. * 115 



48. Cambarus spinosus. 



Plate IX. tigs. 7, 7', 7 a. 7 a' (flrst abdominal appendages of male). 



Cambarus sinnoms, Bundv, rroc. Acail. Nat. Sci. Pliila., LS77, p. 173. 

 Cambarus sj)i/iosus, Faxo.n, Proc. Amcr. Acad. Arts aud Sci., XX. 14S, 1S84. 



Male, form II. — Rostrum broad, excavated, the raised margins parallel 

 and continued back on the carapace between the post-orbital ridges, an 

 impressed ciliated line on each margin ; acumen long, acute, with well- 

 developed lateral teeth at base. Post-orbital ridges sulcate without, with 

 short anterior spines. Carapace ovoid, smooth and punctate above, lightly 

 granulated and ciliated on the sides, lateral spines single, long, acute ; cervi- 

 cal groove not sinuous ; small branchiostegian spines ; front border of cara- 

 pace a little angulated behind the antennae ; areola moderately wide, of 

 equal width before and behind, punctate, equal in length to half the di.s- 

 tance from cervical groove to lateral rostral spines. Abdomen equal to the 

 cephalothorax in length, mostly smooth, proximal segment of telson bispi- 

 nose on each side. Epistoma wide, emarginate in front. Antennna long (as 

 long as the body or longer) ; scale as long as the rostrum, narrow, widest 

 in the middle, thence tapering gradu.ally to the long, sharp, apical tooth ; 

 external border inflated, turned outward at the distal end. Third pair of 

 maxillipeds hairy without, naked below. Chela of moderate size, punctate 

 above, smooth below, a double row of ciliated tubercles on the inner l)order 

 of the hand ; fingers of moderate length, .slightly gaping at base, costate 

 and ciliate-punctate, toothed and ciliate on inner boi'der; outer margin of 

 movable finger with two or three rows of tubercles. Carpus tuberculate 

 above, internal border with a large, curved, sharp median spine, and a small 

 anterior and posterior spine ; below there is a large median spine on anterior 

 margin, and a smaller one at the point of articulation with the hand. Mercs 

 with two obliquely disposed spines near the distal end of superior border; 

 the outer row of the biserial spines beneath consists of the two distal spines 

 alone. Third pair of legs hooked. Anterior pair of abdominal appendages 

 very long, reaching forward to the base of the large claws, deeply bifid, rami 

 slender, blunt-pointed, outer ramus longer than the inner, a little recurved 

 at the tip. 



Male, form I. — According to Bundy, the hooks on the third legs are 

 larger ; first pair of abdominal appendages " strongly bifid, ti2;)S of equal 

 length, very slender, straight, separating at node ; anterior margin with a 



