CRANGON. 
CANCER. Linne. 
ASTACUS. Pennant. 
CRANGON. Fair., Latr., Bose , Leach. 
Antennce superiores setis duabus in eadem fere linea horizontali insertis : interiore longiore. 
inferiores corporis longitudine setaceae decrescentes squama ad apicem externe uni- 
dentata pedunculo adnexa : articulo primo ad squamas medium non producto. 
Palpi pediformes articulis quatuor exsertis : duobus ultimis longitudine aequalibus ; hoc apice 
obtuso. 
Pedes decern : par anticum majus compressum subdidactylum ; pollice brevissimo : par secun- 
dum elongatum tenue didactylum : par tertium tenue praecedente longiore suberassiore 
ungue simplici instructum : paria 4 et 5 prmcedente crassiora unguibus compressis 
instructa. 
Abdomen 6-articulatum. , 
Cauda pentaphylla : lamellis lateralibus angustis. 
Upper antennae with two setae inserted in nearly the same horizontal line ; the inner one 
longest. Under antennae as long as the body, setaceous, with a large scale, having its apex 
externally armed with a spine, at their base : first joint not produced to the middle pf the squama. 
Pediform palpes with four exserted joints ; the two last equal in length ; the latter with the apex 
obtuse. Legs ten : anterior pair largest, compressed, subdidactyle, with the thumb very short : 
second pair elongate, slender, didactyle : third pair slender, longer, and rather thicker than 
second pair, furnished with a single claw : fourth and fifth pairs thicker than the preceding, 
with compressed claws. Abdomen six-jointed. Tail composed of five plates ; the lateral ones 
narrow. 
