PISA. 
CANCER. Pennant , Herbsl , Montagu. 
INACHUS. Fabricii. 
MAJA. Latreille , fiosc. 
PISA. Leach. 
BLASTUS. Leach. 
Antenna externa setacea?, hirt®, pilis basilaribus clavatis, articulo primo secundo multo Iongiore, 
P edipalpi gemini extend caulis interni articulo secundo ad apicem internum emarginato aut 
truncato. 
Pedum par anticum majus crassius (Maris corpore longius, Fajminae corporis longitudine) ; 
paria octo postica mediocres, unguibus denticulatis apice nudis. 
Abdomen 7-articulatum. 
Testa subtriangularis, villosa, tuberosa, antice rostro laciniis divaricatis terminata. 
Ocidi peduuculo vix crassiores. 
GENERIS DIYISIONES. 
* Testa densius villosa, latcribus utrinque postice spina terminatis. (Pisa. Leach.) 
** Testa villosa lateribus spinosis. (Blastus. Leach.) 
External antennae setaceous, hairy, the lowest hairs clubbed, the first much larger than the 
second joint. External double footpalpes with the second joint of their internal footstalk 
notched or truncate. Anterior pair of legs didactyle and thicker than the rest; of the male 
larger than the body; of the female the length of the body: other legs moderate in length, 
armed with claws having naked tips and their internal edge denticulated. Abdomen 7 -jointed. 
Shell somewhat triangular villose, tuberose, terminated in front by a bifid rostrum with divari- 
cating points. Eyes scarcely thicker than their footstalks. 
DIVISIONS OF THE GENUS. 
* Shell more thickly villose, the sides behind terminated by a spine. 
** Shell villose, with spiny sides. 
Of the economy and mode of life of this genus nothing is known. 
