1896.] A. Alcock — Carcinological Fauna of India, 135 



No one who has examined any of the deep-sea Dorippoids can, I 

 think, find any difficulty in accepting De Haaii's comprehensive views 

 of the I'clations of the Oxystorna. 



For instance, in the Indian genus Cymonomops* (which difi*ers but 

 little from Cyclodoripjpe), although the general external form is as 

 plainly as possible that of Dorippe, yet a detailed examination shows a 

 number of Raninoid characters : — The chelipeds are Raninoid, so are 

 the external maxillipeds (especially in their long nariow merus and 

 short narrow exognath), so are the antennules> the fact also that the 

 afferent branchial oj)enings are not in front of the bases of the cheli- 

 peds is suggestive. In Oyclodorippe, moreover, the oviducts open, as in 

 the Baninidfe, on the bases of the third pair of legs. 



We have, in fact, in some of these deep-sea forms the clearest 

 evidence of the close relation of the Ranina type to the Dorippe type, 

 and quite sufficient justification for accepting De Haan's scheme of the 

 Oxystorna almost without modification. 



The following is a list of the known Indian genera of Oxystomes : — 



Calappidse Calappinse : — Calappa, Mursia, Cryptosoma. 



Calappidse Matutinse " — Matuta. 



Leacosiidse Leucosiinse : — Aotdeomorplia, OreopJiorus, Ties, Hetero- 

 Qiucia (nov.), Ebalia, Nursia, Nucia, Parilia, Ra7idallia, Myra, Leiicosia, 

 Oiiychomorpha, Fhilijra, PseudopJnJyra. 



Leucosiidse Iliinse : — Myrodes, IpMculus, ParipJuculus (nov.), Nurs- 

 ilia, Heterolithadia, Arcania, Ixa. 



Dorippidae Dorippinse : — Dorippe, Ethusa. 



Dorippidse Tymolinse : — Gyriionomops. 



Ranimdae : — Notopus, Uanivoides, Lyreidus. 



Tribe OXYSTOMA or LEUCOSOIDEA. 



Oxystomes, Milne-Edwards, Hist. Nat. Crust. II. 96 (partim), and Baniniens 

 Milne-Edwards op. cit. II. 190. 



OxYSTOMATA, De Haan, Faun. Japon. Crust. pp. 111-119. 



Leucosoidea vel Oxystomata, Dana, U. S. Expl. Exp. Crust. I. 389, and Raninidea 

 vel Anomura Leucosidica, Dana, op. cit. pp. 400, 403. 



Oxystomata or Leucosiidea, Miers, Challenger Brachyura, p. 337, and Raninidea, 

 Henderson, Challenger Anomura, p. 26. 



Oxystomata, Ortmann, Zool. Jahrbuch., Sysfc., VI. 1892, pp. 550, 551. 



Epistome reduced or absent. The efferent branchial channels term- 

 inate in the middle of the buccal area, the buccal cavern is therefore 

 produced forwards and is generally of an elongate triangulai' shnpe ; 

 and the efferent channels themselves, whether covered by the external 

 maxillipeds or not, are immediately closed in by an elongate lamellar 

 process of the exopodites of the first maxillipeds. 



* Illustrations of the Zoology of the ' Investigator,' Crustacea pi. xiv. fig. 9, 



