ii8 Records of the Indian Museum. [Vol. \'II 



characters of the mouth parts, in the relative length oi the peraeo- 

 pods and the spinulation of their meral and carpal segments, in 

 the branchial formula and in the armature of the telson there 

 appears to be the closest possible resemblance between the two 

 forms. 



In point of fact, the sole difference that I have been able to 

 discover is one of colour. In the majority of the New Zealand 

 specimens received from Dr. Chilton the proximal part of each of 

 the setae which fringe the antennal scale and uropods is bright 

 purple and the same coloration is found on the terminal spinules 

 of the telson. This curious pigmentation undoubtedly vanishes 

 in alcohol and, although it is well shown in most of Dr. Chilton's 

 specimens, which were collected in 1910, it could hardly be ex- 

 pected to have persisted in the examples from Assam which have 

 been lying in alcohol for many years. 



Xiphocandina curvirostris was fir.st described by Heller (1862) 

 as a species of Caridina from specimens obtained at Auckland. A 

 fuller account by the same author appeared in 1865 and in 1876. 

 Miers included it, also under the genus Caridina, in his Catalogue 

 of New Zealand Crustacea. Three years later (1879) Thomson des- 

 cribed it as a new species of Palaemonidae, Leander fluviatilis ; 

 but in 1903 he realized his mistake and gave a fresh account of it ^ 

 under the name Xiphocaris curvirostris. In Ortmann's revision of 

 the Atyidae (1895) it appears as Caridina curvirostris with a note 

 to the effect that it probably belongs to the genus Xiphocaris. 

 Bouvier does not refer to the species in his valuable paper published 

 in 1905 ; but he mentions it subsequently — using Thomson's name. 

 fluviatilis — as a member of his new genus XipJiocaridina (1909, 



The curious distribution of Xiphocaridina curvirostris does 

 not, I believe, find an}'- exact parallel among other freshwater 

 Crustacea. 



Perhaps its most peculiar feature is that the other species of 

 the genus, X. compressa, which inhabits S. Australia, Flores, China. 

 Korea and Japan appears to extend in a band completel^^ separat- 

 ing the two localities in which it is known to exist. But in the 

 present state of our knowledge it is impossible to lay any emphasis 

 on this point, for it may well be that X. curvirostris still remains to 

 be discovered in many other localities. 



On turning to Ortmann's work on ■' The geographical distribu- 

 tion of freshwater Decapods and its bearing on Ancient Oeograi)hy " 

 (1902) it is at once seen from the maps illustrating the hypotheti- 

 cal distribution of land and sea in past geologic periods that, 

 according to this author's views, no direct land connection be- 

 tween New Zealand and Assam has existed in any recent epoch. 

 In the Lower Cretaceous, however, when a land-l:)ridge connected 

 S. India with ^Madagascar and S. Africa, and when the whole of 

 Northern India was submerged and formed the eastern limit of the 



1 The figures given on PI. xxix are poor. 



