1896.] A. Alcock — Carcinological Fauna of India. 275 



situated in front of the bases of the 

 ehelipeds, a bridge of the carapace in- 

 tervening Dorippe. 



2. The anterior extremity of the buccal 

 cavern either stops at, or does not reach 

 as far as, the basal joint of the anten- 

 nules : the afferent branchial openings 

 are situated immediately in front of the 



bases of the ehelipeds Ethusa. 



II. The external maxillipeds are greatly elongate 

 and do not leave any appreciable portion of 

 the buccal cavern uncovered : the afferent 

 branchial openings are not situated in front 

 of the bases of the ehelipeds Cymonomops. 



Dorippe, Fabricius. 



Dorippe, Fabricius, Ent. Syst. Suppl. p. 361. 

 Dorippe, Milne Edwards, Hist. Nat. Crust. II. 154. 

 Dorippe, Miers, Challenger Brachyura, p. 327. 



Carapace very flat, truncate-triangular and broadest behind, cover- 

 ing little more than the first two thoracic sterna, its regions well 

 defined, the hepatic region small. 



The front consists of two flat triangular teeth : on either side of it, 

 in the same plane, are (1) a hood-like fold covering the base of the long 

 completely exposed geniculate eyestalks, and separated by a deep 

 narrow fissure from (2) a long flat triangular tooth, formed by the 

 prolongation of the antero-external angle of the carapace, and forming 

 the outer angle of the orbit. The floor of the orbit is even more incom- 

 plete than the roof, and is formed almost entirely by the base of a great 

 projecting spine at the inner cantlius, but even this spine may be rudi- 

 mentary. The antennules fold longitudinally, they are too large to fold 

 into the fossettes. The antennas also are rather large : the basal joint 

 is wedged in between the front and the spine at the inuer canthus of 

 the orbit. 



The buccal cavern is abruptly narrowed anteriorly and prolonged 

 as a deep well defined canal to, or even slightly beyond, the front : the 

 canal is closed in below by long stout foliaceous processes of the first 

 maxillipeds. The external maxillipeds do not cover this canal : their 

 flagellum or palp arises at the outer angle of the long narrow merus 

 and is completely exposed in flexion. The afferent branchial orifices 

 are oblique pocket- like slits in the pterygostomian region. J 



