CAMBARUS. 115 
48. Cambarus spinosus. 
Plate IX. figs. 7, 7', 7a, 7a! (first abdominal appendages of male). 
Cambarus spinosus, Bunpy, Proce. Acad. Nat. Sci. Phila., 1877, p. 173. 
Canbarus spinosus, Faxon, Proc. Amer. Acad. Arts and Sci., XX. 148, 1884. 
Male, form IT.— 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 suleate 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 antenna ; areola moderately wide, of 
equal width before and behind, punctate, equal in length to half the dis- 
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. Antenne long (as 
long as the body or longer); scale as long as the rostrum, narrow, widest 
in the middle, thence tapering gradually 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 border 
of the hand; fingers of moderate length, slightly gaping at base, costate 
and ciliate-punctate, toothed and ciliate on inner border; 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. Meros 
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, tips of equal 
length, very slender, straight, separating at node; anterior margin with a 
