66 CAPRELLID^E. 



Caprella acwninifera. LATREILLE, in Nouv. Diet. d'Hist. Nat. 2nd Edit, 

 vi. p. 433. DESMAREST, Consid. Crust, p. 277 

 (not of Johnston). SPENCE BATE, Ann. Nat. 

 Hist. 2 ser. xix. p. 151. 



THIS species may readily be detected from any other 

 by the peculiarly vaulted or skull-like head, together 

 with the tuberculated character of the body. The first 

 segment of the body is short. The three next are longer 

 than the first, equal to each other, and surmounted by 

 three dorsal blunt teeth, or tubercles. The two anterior, 

 immediately over the articulation of the second pair of 

 legs, are sublateral and parallel. The third is central, and 

 situated upon the posterior margin. The last three seg- 

 ments are short, and each is furnished with only two 

 sublateral parallel tubercles, which are surmounted by nu- 

 merous small, bead-like tubercles. The superior antennae 

 are not half the length of the animal. The inferior 

 antennae are not longer than the peduncle of the superior. 

 The first pair of legs are small, the hand being ovate 

 and the palm slightly convex and imperfectly defined. 

 The second pair of legs articulate with the second seg- 

 ment of the body, posteriorly to the centre. They have 

 the hand in the male very large, rounded on the back, 

 and hollow below (in some specimens we have seen 

 inflated membranous sacs filling the palm), being defined 

 posteriorly by a sharp tooth, and armed anteriorly with a 

 small point that marks the position where the lateral 

 walls of the palm unite together anteriorly. The finger 

 is much curved, and armed with two obtuse teeth upon 

 the inner margin. The three posterior pairs of legs are 

 of equal length, and adapted for prehensile use. 



In the female the tubercles upon the back are less 

 conspicuous than in the male, and the second pair of legs 

 have the hand smaller, of an oval form, the palm being 

 slightly convex, defined by a small process, armed with 



