50 GENUS CERAPUS. 



nearly equal; exterior antenna five-jointed, the first joint 

 placed in a deep sinus beneath the eye, short, not pro- 

 jecting beyond the margin of the head above, second 

 joint hardly longer than the first, third and fourth equal 

 to the second and third of the interior antennae. Ante- 

 rior pair of feet moderate, with a small ovate hand and 

 moveable nail, not closing on the hand, attached to the 

 first segment of the body; second pair with the basal 

 joint attached to the edge of the body (as in Cymothoa, 

 &c.) second joint broad, compressed with an insisure 

 near the base before, third small, medioliform, carpus 

 cylindrical, narrower than the preceding joint; hand very 

 large, compressed, subtriangular, attached to the carpus 

 by the inferior edge of the acute angle, which is a little 

 curved, tip emarginate and armed with a strong, acute 

 spine on the anterior angle, thumb two-jointed, first joint 

 incurved, linear, second acute, closing on the spine of the 

 h^nd. Third and fourth pairs of feet equal, similar to 

 each other, first joint dilated, equal to that of the preced- 

 ing feet, remaining joints small, nearly equal to each other, 

 submoniliform; two posterior pairs of feet reflected above 

 the back; tail incurved, furnished each side near the tip 

 wi^h a pedunculated bifid process, and a minute, conic, 

 acute, papilla. 



1 . C tuhulcir'is. Head with a mucronate carina before; 

 eyesi oval, black. Hand and first joint of the thumb of 

 tlie second pair of feet with one or two obtuse teeth within. 

 Body above blackish, with irregular paler spots; antennae 

 and feet white, joints tipped with blackish; two hind pairs 

 of feet and tail white. 



Inhabits a tube. Length about one quarter of an inch. 



This curious animal, for which I have constructed a 



