120 A REVISION OF THE ASTACIDA. 
= 
and narrow, horny-tipped ; lateral spmes small. Post-orbital ridges not very 
prominent except anteriorly, where they terminate in a spine with a corne- 
ous tip. Carapace cylindroidal, punctate above, granulated on the sides, 
antero-lateral margins bluntly angulated ; cervical groove sinuate ; small and 
acute lateral spine; no branchiostegian spine; areola of moderate width, 
punctate. Abdomen as long as the cephalothorax; telson rounded behind, 
bispinose on each side. Epistoma smooth, anterior process triangular, in. 
some specimens truncate. Thoracic sterna with silky seta at bases of the 
legs. Antenne slender, as long as the body; scale a little longer than the 
rostrum, of moderate width, subtruncate at distal end, outer margin ending 
in a long, sharp, somewhat outwardly directed spine. Third pair of mawxilli- 
peds hairy within. Chelipeds short, stout; chele large, wide, with slender 
cylindrical, widely gaping fingers, which are curved outward at the base and 
opposable only at their tips; hand thickly punctated above and below, inner 
margin obscurely serrate ; fingers naked at base, with parallel rows of ciliated 
dots; a dark band around both the inner and outer fingers a little distance 
from the tip. Carpus punctate above, with a strong, sharp internal median 
spine; below there is no anterior median spine, and only a very minute ex- 
ternal one. Meros short; of the biserial inferior spies only the distal one 
in each row is usually developed to any extent; above there are commonly 
two obliquely placed ante-apical spines, in some specimens only one. Distal 
portion of the following pairs of legs furnished with long seta, especially 
long on the second pair of legs. Third segment of third pair of legs hooked. 
First pair of abdominal appendages long, deeply bifid ; rami slender, straight, 
parallel, the outer a little longer than the inner, and a little recurved at the 
tip; im some specimens the anterior border at the base of the rami has a 
projecting angle or shoulder, but in most specimens this is not evident. 
Female. — Fingers straighter. Base of external finger has a dense beard 
on the inside; in a few of the specimens seen, the fingers are longer, nearly 
straight, their opposed margins almost meeting throughout their length. 
Annulus ventralis bilaterally symmetrical, anterior margin bituberculate, 
posterior margin unituberculate, fossa transverse. 
_ Dimensions of a male, form I.— Length of body, 38 mm. Length 
of carapace, 19.5 mm. Length of abdomen, 18.5 mm. From tip of ros- 
trum to cervical groove, 14 mm. From cervical groove to posterior bor- 
der of carapace, 6mm. Length of rostrum, 5 mm. Length of acumen of 
rostrum, 2 mm. Width of areola, 1mm. Length of antenna, 36 mm. 
