I(;i* AMPHIPODA NORMALIA. 



margin imperfectly toothed and slightly concave ; dactylos half 

 the length of the propodos, internal margin entire. 

 Hah. Valparaiso. 



In other respects the animal, as represented by Nicolet, bears a 

 very close resemblance to A. (jracUls. 



51. STIMPSONIA, n. g. 



Slender ; the inferior pair of antennte considerably longer than the 

 superior. First pair of gnathopoda larger than the second ; carpus 

 broader and longer than the propodos : second pair imperfectly 

 chelate, having the carpus much longer than the propodos. Poste- 

 rior pereiopoda long. Posterior pleopoda biramous. Telson tubular. 



The name given to this genus is in compliment to the industrious 

 and intelligent natui-alist of the United States Exploring Expedition 

 to the Xorth Pacific. 



1. Stimpsonia chelifera, n. s. (Plate XXIX. fig. 9.) B.M. 



Eyes small, round, black. Superior antennae ha\'ing the first joint of 

 the peduncle scarcely as long as the cephalon, second joint quite 

 as long, third but half the length of the second ; flageUum reach- 

 ing to the thii'd or fourth articulus of the flageUum of the inferior 

 pair ; secondary appendage uniarticulate. Inferior antennae two- 

 thii'ds the length of the entire animal ; third joint of the peduncle 

 dilated, nearly as broad as long, the fourth reaching beyond the 

 extremity of the second of the superior, fifth considerably longer 

 than the fourth ; flageUum nearly as long as the fourth joint of 

 the peduncle. First pair of gnathopoda having the carpus and 

 propodos associated ; cai-pus longer and broader than the propodos, 

 and from the centre of the inferior margin a long, slender, curved, 

 sharp tooth is produced anteriorly to nearly the extremity of the 

 propodos ; propodos arcuate, scarcely more than one-third as 

 broad as long, inferior margin paraUel with the superior, palm 

 rudimentary ; dactylos long, curved, and serrated upon the inner 

 margin, antagonizing with the long tooth upon the cai-pus. Second 

 pair of gnathopoda ha\4ng the carpus much longer than the pro- 

 podos, not inferiorly produced ; propodos as broad as long, the 

 palm deeply waved ; infero-anterior angle produced into a long, 

 stoxTt, slightly posteriorly cui-ved blunt tooth, against which the long 

 dactylos impinges, and with it forms an imperfect claw. The 

 rest of the animal closely resembles Aora gracilis. Coloui' of the 

 animal generally dark grey, of the antennae red. 



Length Vxiths of an inch. 



Hab. Salcombe {Mr. Webster). 



