526 Dr. A. Alcock — A Revision 



Tiiirty-oue females and a male have l)een collected in the 

 following localities : — Off the Malabar coast (Mangalore) in 

 21-2G fathoms ; off the Orissa and Ganjam coasts in 20-68 

 fathoms ; off the Vizagapatam coast in 7o-23 fathoms ; and 

 oft' the sonth coast of Ceylon in 20 fathoms. 



In the single male the rostrum is broken. 



This species is distinguished from all those Indian Para- 

 penei which have longitudinal and transverse carapacial 

 sutures by the absence of a branchiostegal spine from the 

 antero-inferior angles of the carapace. 



3. Metapeneus stridulans (Wood-jMason^ MS.). 



Q'otalocaris stridulans, Wood-Mason, MS. (name only). 



Of this species we possess about 130 specimens dredged 

 by the ' Investigator/ and one, identified by S[)ence Rate as 

 Peneus velulhms, Dana, from the ' Challenger ' collection. 



The species may probably prove to be identical with the 

 Parapeneus akayebi of Miss Rathbun. 



It is characterized by the presence in both sexes of a pair 

 of stridulating-organs, situated one on each side of the 

 carapace, near the middle of the posterior end of the 

 branchiostegite, in such a way that the anterior edge of the 

 first abdominal tergnm can play over them. Each organ 

 consists of a longitudinal row of vertically disposed ridges, 

 which vary in number^ being usually five, seldom less than 

 five, and occasionally as many as twelve. 



The species is a tyjncal Metapeneus, and belongs to the 

 same group as M. phUippinensis and coniger. 



Integument remarkably thick, hard, and tomentose. 



Rostrum nearly straight, upiilted, sometimes reaching to 

 the end of the antennular peduncle, but often shorter, armed 

 dorsally with 5-8 teeth, the last of which is small and 

 isolated (epigastric). No postrostral crest. An indistinct 

 postocular denticle. Postantennular (antennal) spine very 

 strong, produced backwards as a strong convexity defining a 

 broad postantennular sulcus. Hepatic spine small ; cervical 

 groove present only in its neighbourhood. Branchial region 

 not defined except by a short crescentic crease below the 

 hepatic spine. Antero-lateral (antero-inferior) angles of 

 carapace spiniform. A pair of stridulating-orgaus as already 

 defined. 



The second abdominal tergum is medially carinated in 

 less than its posterior half, the third in almost all its extent, 

 the carina in both cases being sulcate ; the fourth to sixth 

 are all sharply carinated^ the carina of the fourth and fifth 



