152 
CLASS CRUSTACEA. 
arching of the edges of the testa terminates posteriorly by a 
fold, and a projection jutting out in the manner of an angle. 
Those whose front is tridenticulated, and whose testa pre- 
sents on each side only this projection or posterior tooth, 
compose Dr. Leach’s genus Carpi Hus* The species of this 
subdivision ( C. corallinus , Fab. ; C . macalatus ejusd.) have 
marblings, or round spots, of the colour of blood, ( Xantho 
of the same.) Other considerations might induce us to aug- 
ment the number of these sections. But we have thought 
proper to confine ourselves to an indication of the principal 
ones. 
Pirimela, Leach , 
Altogether resemble the crabs, but their external antenna? 
are remarkably extended beyond the forehead, and their stem, 
longer than the pedicle, is composed of a great number of ar- 
ticulations. The fossets of the intermediate are, as well as in 
C ’. pagurus , rather longitudinal than transverse. But one 
species known, (P. denticulata , Leach.) 
Atelecyclus, Leach , 
Have, as well as the pirimelse, the fossets of the intermediate 
antennae longitudinal. The lateral antennae are elongated, 
projecting, and composed of a great number of articulations. 
But they are very setaceous, as well as the claws ; these claws 
are strong, with the hands compressed. The third articula- 
tion of the jaw-feet is sensibly narrowed above, in the manner 
of an obtuse, or rounded tooth. The tarsi are conical, and 
the ocular pedicles are of the ordinary size. The tail is more 
elongated than in the preceding Crustacea. 
