1915-] Fauna of the Chilka Lake : Crustacea Decapoda. 315 



setae, among which, in the posterior half of each, a sharp backwardly directed spine 

 may be detected. 



The telson (text-fig. 352) reaches beyond the end of the uropods and is strongly 

 sulcate above. Apart from those at the apex there are only two pairs of dorsal 

 spines ; the first pair is situated near the anterior margin of the telson ; the second 

 about in the middle of its length. At the apex are five pairs of spines, the respective 

 lengths of which are shown in text-fig. 35/. l Except for the outermost, all these 

 spines are internally pectinate, the innermost being also pectinate externally. 



The outer uropod is a little more than three times as long as wide. The straight 

 outer margin terminates in two spines in front of which are from 8 to 11 additional 

 spines interspersed among fine setae. At the apex of the inner uropod on its dorsal 

 side there are also three or four slender spines. 



Large specimens attain a total length of about 16 mm. 



Indian specimens differ in several points from Paulson's figures and from the 

 translation of his description which Nobili has supplied. The individual drawn by 

 Paulson in fig. 1 is apparently a female and, if I am right in assuming that the 

 Indian examples belong to the same species, the lateral ridges on the carapace on 

 either side of the middle line are incorrectly shown. These ridges should be parallel 

 and should extend further backwards 



Leptochela robusta, Stimpson, judging from de Man's account of a single male' 2 , 

 is apparently a very close ally of L. aculeocaudata; but, apart from less conspicuous 

 details, differs from it in the armature of the telson. According to de Man's descrip- 

 tion there are in this species three pairs of spines on the upper surface of the telson, 

 the posterior pair situated about in the middle of its length. In L. robusta, also, 

 there are four pairs of spines at the apex of the telson in place of the five found in 

 L. aculeocaudata. 



In life specimens are transparent with the oral appendages, the bases of the 

 thoracic limbs and pleopods, the hinder half of the last abdominal somite and telson 

 bright red. The carapace, abdomen, antennae, antennules, uropods and the greater 

 part of the thoracic and abdominal appendages are colourless. The eggs are opaque 

 and whitish. 



Of Leptochela aculeocaudata only a single individual was found in the Chilka Lake. 

 It was obtained in the outer channel near Barhampur I. in March in water of specific 

 gravity as high as that of the Bay of Bengal in the vicinity of the lake (1 -0265). The 

 species is clearly no more than a casual visitor to the lake. 



There are numerous other examples of the species in the Indian Museum. In 

 1889 the R.I.M.S. 'Investigator' obtained a specimen 3 miles E.S.E. of Puri (a posi- 

 tion not far distant from the mouth of the Chilka Lake) at a depth of 10 fms. 



1 The spines of the third pair are shorter than the second and fourth and are partially concealed 

 by them. 



2 loc. cit., supra, p. 310 



