45 



21. BciitJicsict/mits Bartletti, S. I. Smith. 



Beniheticymns BartU-i, S. I. Smith, Ball. Ma?. Comp. Zcol. X. 1881-85 - . pj. xiv. figs. 1-7. 



Benihc-ecties Bartletii, S. I. Smith, Albatrc ;? Crnsfe := Eep. U. S. Fish. Coram, for 1SS2, p. 391, pi. t. fig. 8, 

 and for 1SS5, p. S7, pi. ivii:, Gga. -. -:, and Proc. U. S. >' . -. ! I - 1885 p. 508: A. Agussiz, BalL Hob, Comp. 

 Zcol. XV. ISSS, p. 47, fig. 248. 



So far as the male is concerned this species closely resembles B. tn vestigatoris, 

 from which it differs only in the following particulars : — 



(1) the rostrum has only 2 teeth on its dorsal edge : 



(2) only the 5th and 6th abdominal terga are carinated, and the carina of 

 the 5th is armed with a long hooked spine : 



(3) the curved and truncated dactylus of the external maxillipeds has 

 several spines, which are placed at its tip and along it outer edge : 



4 the vertical tooth on the 1st abdominal sternum is even larger. 



Bay of Bengal, off the north-eastern coast of Ceylon, 771-665 fathoms. 



Regd. Xo. — . 



Gennadas, Spence Bate. 



.adas, Spence Bate, Ann. JXag. Xat. Hist., Sept. 1SS1. p. 191 : Challenger Crustacea Macrnra. p. 339. 

 Amalopensus, S. L Smith, Bull. Mus. Comp. Zool. X. 1SS1-S2. p. S6. 



Differs from Benthesicymus only in the following particulars : — 



(1) the exopodites of the 2nd maxillipeds are only about as long as the 

 endopodites, and the endopodites have a thin broad foliaceous oval merus beneath 

 which the 3 terminal joints are concealed in flexion : 



(2) the ischium and merus of the external maxillipeds are also thin broad 

 and subfoliaceous : 



(3) the ischium merus and carpus of the 1st pair of legs are thin broad and 

 compressed : 



(-t) the pleurobranchia? though by no means rudimentary are considerably 

 reduced in size. 



It is doubtful whether it would not be better to regard Gennadas as a 

 subgenus of Benthesicymus. 



- -" Indian spi Gennadas. 



I. The 3rd-cth abdominal terga are carinated : the exopodites of the 1st 

 pair of abdominal appendages are longer than the carapace (and 

 rostrum) ... ... ... ... ... G t carinatus. 



II. Only the 6th abdominal tergnm is carinated : the exopodites of the 



1st pair of abdominal appendages are shorter than the carapace, ... G. parvus. 



