35 



Subgenus Plesiopeneus. 



Plegiopemeus, Bate, Ann. Mag. Nat. Hist., Sept. 1S81, p. 1881 : Faxon. Mem. Mus. Comp. Zool. XVIII. 1895, 

 p. 109 (part). 



Aristseus, Wood-Mason, toe. cit. (part : Aristseus coruscans). 

 Aristaeopsis, Wood- Mason, loc. cit. (part : Aristaeopsis edwardiiana). 



Rostrum 3-toothed, either long in both sexes, or long in the female and of 

 moderate length in the male. Cervical groove either distinct or indistinct. An 

 orbital and branchiostegal spine : no hepatic spine. 



The last 3 or 4 abdominal terga are carinated, each carina ending in a 

 spine. 



The terminal joint of the mandibular palp is triangular, sometimes with its 

 postero-mternal angle much produced. The exopodite of the 2nd maxillipeds 

 is much longer than the endopodite and is compressed and stiffish. The dactyli 

 of the last 2 pairs of thoracic legs are either setiform or lanceolate. 



The 3rd pair of thoracic legs have a podobranch, and the 4th pair an 

 epipodite. The pleurobranchiae in advance of somite XIV, though much re- 

 duced in size, are plumose and functional. 



The branchial formula is as follows : — 



II. 



Synopsis of the Indian species of the subgenus Plesiopeneus. 



Cervical groove indistinct : the carina? of the last 4 abdominal 

 terga end acutely : terminal joint of madibular palp 

 bifurcate owing to the length of the postero-internal angle : 

 dactyli of last 2 pairs of thoracic legs lanceolate 



Cervical groove distinct : only the last 3 abdominal terga are 

 carinated : terminal joint of the mandibular palp simply 

 triangular : dactyli of the last 2 pairs of thoracic legs 

 setiform 



A. (P.) edwardsiantis. 



A. (P.) coruscans. 



