pirimela; 
CANCER. Montagu. 
Antenna externa elongates, setaceee ad oculorum canthum internum inserts . 
interna in foveolis obliquis reponend®. 
Pedipalpi gemini externi cauli interno articulo secundo quadiato, ad apicem internum trunc 
subemarginato palpigero. 
Pedum par anticum ®quale, didactylum ; paria alia ambulatoria, subcompressa : ungues acuti. 
Abdomen Maris 5, FyEMIN/E 7-articulatum. 
Testa subtransversa, margine antico in lineam subsemicircularem arcuato ; orbita supra ac 
infra fissura unica. 
Oculi pedunculo subcrassiores. 
Obs. Mas abdomine articulo quarto quadrato. 
External antennae elongate, setaceous, inserted at the internal corner ot the eyes ; internal 
antenna- placed in oblique excavations. External double pedipalpes with the second joint ot 
their internal footstalks, having the internal apex truncate-emarginate for the insertion ot the 
palpes. Anterior pair of legs unequal, didactyle ; the other pairs formed for walking, sub- 
compressed; claws sharp. Abdomen of the Male with five, of the Female with sev enjoints. 
Shell somewhat transverse, the anterior margin bent in a semicircular line ; orbit above and below 
with one fissure. Eyes somewhat thicker than their peduncles. 
This Genus is distinguished from Carcinus, to which it makes the nearest approach, by 
having the four hinder pair of legs equally compressed, by the greater length of its antenn®, and 
by the form of the fourth segment of the abdomen of the male. 
