NEPHROPS. 
ASTACUS. Pennant. 
NEPHROPS. Leach. 
CANCER. Linné. 
Antenne in eddem linea horizontali inserta : 
Interiores setis duabus ; superiore crassiore compress4; inferiore setaced, tereti. 
Exteriores pedunculo articulo primo squamé ultra pedunculi apicem prodeunte. 
Palpi pediformes articulis quinque exsertis ; articulo primo laiere interiore supra dentato, infra 
subserrulato. 
Oculi maximi, reniformes, pedunculo abrupté et multé crassiores. 
Pedes decem ; par anticum majus, inequale, didactylum ; manu filiformi: paria 2 et 3 didac- 
tyla, filiformia; paria 4 et 5 filiformia, ungue terminata ; ungues acuminati. 
Abdomen sex-articulatum ; segmentis lateribus acutis. 
Cauda pentaphylla; processu exteriore bipartito, articulato. 
Femin4 coxis tertiis, Mas coxis quintis perforatis. 
Se 
Antenne inserted in the same horizontal line: interior ones with two sete ; the upper seta 
compressed ; the under seta setaceous, rounded: exterior antenne witha scale on the first joint 
of their peduncle, extending beyond the apex of the peduncle. Pedipalpes with five exserted 
joints; the first joint with the interior side dentated above, subserrulated beneath. Eyes very 
large, kidney-shaped, much and abruptly thickerthan their peduncle. Legs ten ; anterior pair 
largest, unequal, didactyle ; second and third pairs filiform, didactyle ; fourth and fifth pairs 
filiform, terminated by acuminate claws. Abdomen six-jointed ; the sides of the segments 
acute. Tail with five plates ; the exterior scale articulated. 
The form of the eyes, and the sexual perforations, distinguish this genus from. Astacus. 
