Indian Deep-sea Crustacea. 23 



A male and a female from off the Travancore coast, 

 430 fathoms. 



In the male the carapace is 38 millim. long and the 

 chelipeds 27 millim. 



Colour in life pink. 



This species is not very closely related to any of those 

 with which we are acquainted. In the system of MM. Milne- 

 Edwards and Bouvier (Ann. Sci. Nat. Zool. ser. 8, vol. xvi. 

 1894) it would be placed alongside M. ornata, Faxon, but it 

 is very different from that species. It well illustrates the 

 difficulties that attend the splitting-up of Munidopsis into 

 subordinate genera, for it might almost equally well be placed 

 with Elasmonotus or with Orophorhynchus, although it is 

 unlike the typical species of those genera. 



Ptychogaster, A. Milne-Edwards. 



[Ptychogaster, sp. 



A single very small specimen from off the Maldives, 

 459 fathoms, is so closely similar to P. Milne- Edwardsi, 

 Henderson, from off the Patagonian coast, that we do not feel 

 justified in giving it a distinctive name, but await further 

 material.] 



Ptychogaster Hendersoni, sp. n. 



Carapace (including rostrum) equal in length to the first 

 six fully extended abdominal terga, covered with spinulesand 

 spines, in which a definite serial arrangement of the larger 

 spines is hardly manifest. 



All the abdominal terga (telson excepted) and pleuree bear 

 spines : the first tergum has a transverse spiny carina con- 

 tinuous with a similar carina on the anterior edge of the 

 second pleura? ; the second has two such carinas; the third 

 has a longitudinal row of spines at the junction with either 

 pleura ; the fourth and fifth have two transverse series of 

 spines, besides an occasional spine on their posterior edge ; 

 the sixth has numerous spines, including three conspicuous 

 transverse series. 



First segment of the telson not much more than half the 

 length of, and slightly broader than, the second. 



External maxillipeds unarmed, except for the fine teeth 

 along the inner edge of the ischium, hairy along inner edge, 

 especially at distal end. 



Chelipeds and legs long, slender, and spiny ; in the female 

 (male unknown) the chelipeds are more than 2^ times the 



