120 



GAMMARIM. 



AMP HIP OD A. 



NATATORU. 



LYSIANASSIDES. 



CALLISOMA CRENATA. 



Specific character. Inferior antenna one-third the length of the animal. 

 First pair of gnathopoda having the dactylos developed into a thick brush of 

 short hair. Fourth segment of the pleon having on the dorsal surface a deep 

 notch. 



Length, ^ inch. 



Callisoma crenata. SPENCE BATE, Gat. Arnph. Brit. Mus. p. 85, pi. 



xiv. fig. 5. 

 Scopelocheh'us crenatus. SPENOE BATE, Brit. Assoc. Hep. 1855, p. 58. 



Synop. &c., Ann. Nat. Hist. xix. 138 (1857). 



WHITE, Hist. Brit. Crust, p. 167. 



THIS species is very round and smooth, and rolls itself 

 up almost into a ball. The head is small, and anteriorly 

 produced into a minute flat rostrum, which is merely a 

 projecting portion of the skin, extending horizontally with 

 the top of the head. The antero-inferior angle projects 

 as far forwards as the extremity of the rostrum. The 

 eyes are small and reniform, showing black spots on a 



