274 



Memoirs of the Indian Museum. 



[Vol.. V, 



The forms described by Ortmann l under the names Leander longirostris var. 

 japonicus and var. carinatus are now regarded as distinct species.' 2 The specimens 

 recorded by de Man (loc. cit.) under the name Leander sp. are almost certainly young 

 examples of L. styliferus. 



Leander styliferus is extremely common in brackish water in the Sunderbuns 

 and the Gangetic delta , the locality from which the original specimens described by 

 Milne-Edwards were obtained. It is also recorded by Henderson and Miss Rathbun 

 from Karachi and by the former author from Mergui and the Gulf of Martaban. 



The species is evidently nothing more than a casual visitor to the Chilka Lake. 

 The single specimen obtained was found at Satpara in March 1914, in water of the 

 same salinity as that of the Bay of Bengal in the vicinity. 



Genus UROCARIS, Stimpson. 



i860. Urocaris, Stimpson, Proc. Acad. Nat. Sei. Philadelphia, XII, p. 39. 

 1902. Urocaris, Rathbun, Bull. U.S. Fish Comm. for 1900, XX, ii, p. 126. 



Urocaris is one of the genera which lie on the border-line between the Ponto- 

 niidae and Palaemonidae, families which until recently have been regarded as dis- 

 tinct. The absence of a palp on the mandible and the rather deeply cleft outer 

 antennular flagellum induced most authors to regard it as an ally of Palaemonetes, 

 but Sollaud 3 has very correctly pointed out that the reduced gill-formula and the 

 presence of three pairs of spines at the apex of the telson indicate a position near 

 Periclimenes and other less specialized genera of the old Pontoniidae. 



In the species of Urocaris, found in the Chilka Lake, the branchial formula is as 

 follows: — 





VII 



VIII 



IX 



X 



XI 



XII 



XIII 



XIV 



Exopods 



1 



1 



1 













Podobranchs 



ep. 



ep. 



ep. 



, . 



, . 



, . 



. . 



. . 



Arthrobranchs 





, t 



1 



, m 



, , 





. . 



, . 



Pleurobranchs 









1 



I 



I 



I 



I 



This formula is almost identical with that found in Periclimenes, from which, 

 however, Urocaris may be separated by the more deeply cleft outer antennular flagel- 

 lum and by the great length of the last abdominal somite. In Urocaris, also, the 

 inferior portion of the rostrum, i.e. that situated below the midrib, is ill-developed 

 or absent and ventral teeth, if present, are placed close to the apex. These char- 

 acters are not very convincing, though, in combination, they give the typical species 

 of the genus a very distinct faciès. 



1 Ortmann, Zool. Jahrb., Syst., V, pp. 519-521, pi. xxxvii, figs. 14, 142. 



a See Rathbun, loc. cit., and Doflein, Abhandl. k. bayer. Akad. Wiss., XXI, p. 639, pi. iii, fig. 8 (1902). 



3 Sollaud, C. R. Acad. Sei., Paris, Dec, 1910, p. 1. 



