118 A REVISION OF THE ASTACIDA. 
49. Cambarus Putnami. 
Plate V. fig. 5, Plate IX. figs. 6, 6’, 6a, 6a’. 
Cambarus Putnami, Faxon, Proc. Amer. Acad. Arts and Sci., XX. 131, 1884. 
Male, form I. — Rostrum broad, subexcavated, margins nearly parallel, 
with a line of ciliated puncta; acumen long, equal in length to the width of 
base of rostrum, narrow, acute, with a black horny tip and lateral spines. 
Post-orbital ridges suleate on external side, inflated at posterior end, armed 
with a sharp, horny-tipped anterior spine. Carapace long-oval, slightly flat- 
tened above, heavily punctated, sides rough with ciliated granules; cervi- 
cal groove deep, lightly sinuate, broken on the sides just above the small, 
acute lateral spine; branchiostegian spine slightly developed ; anterior lat- 
eral margins angulated, but without sub-orbital spine. Posterior segment 
of carapace equal in length to half the distance from tip of rostrum to 
cervical groove. Areola of moderate width, punctated. Abdomen as long 
as cephalothorax, pleura punctate, telson bispinose on each side. Ante- 
rior process of epistoma ciliated, triangular, sides convex, marginate. Basal 
segment of antennule armed below with an internal ante-apical spine. An- 
tenn slender, about as long as the body, scale as long as the rostrum, of 
moderate width, external border inflated, ending in a sharp spme. Third 
maxillipeds hairy within and below. Chelipeds stout; chela large, external 
margin convex ; hand ciliate and punctate above and below (the dots large), 
swollen above, internal border of moderate length and furnished with two or 
three rows of depressed ciliated tubercles; fingers gaping at base, at least in 
large individuals, costate and punctate-lined, external margin of movable 
finger with depressed ciliated tubercles irregularly disposed in two rows; 
tips of fingers incurved, horny. Carpus smooth or faintly tuberculate above ; 
a large, acute median internal spine, and small proximal and distal internal 
spines ; beneath, the carpus has a very minute or no median anterior spine, 
a short and acute external spine. Meros with two superior obliquely placed 
ante-apical spines ; of the ordinary biserial inferior spines only the distal one 
or two of the outer row are developed. Third pair of legs hooked on third 
segment. Thoracic sterna hairy. First pair of abdominal appendages very 
long reaching the base of the chelipeds when the abdomen is flexed, tuber- 
culated\on internal border at the base, deeply bifid; rami slender, acute, 
forming ai acute angle with the basal part, the outer slightly recurved, the 
