I9I5-] 



Fauna of the Chilka Lake : Crustacea Decapoda. 



273 



The specimens yield the following measurements (in mm.) : — 





J3 

 -t-> 



00 

 Ö 

 Ol 



1 — 1 



4-1 







eu 

 



a. 



t-c 

 



O 



XI 

 +J 



OJD 



n 



Length of right 

 chelipede. 



Length of left cheli- 

 pede. 



Larger chelipede : 

 length of 







h- ( 



cri 

 3 

 u 

 <v 



Cf) 



D 

 Oh 



ai 







S 



Dactylus. 1 



1 



54 

 47-8 



14-4 



12-0 



33 

 26-3 



3i'5 

 30-6 



5'2 



47 



67 



6-3 



7-0 

 6-i 



68 

 6-8 



5-8 

 5'4 



P. scabriculus must be regarded merely as an occasional visitor to the lake. It 

 is evidently very scarce and there is little likelihood that it ever breeds in the water 

 near Rambha which, throughout the year, retains some trace of salinity. At the 

 time the specimens were obtained the specific gravity of the water in this neighbour- 

 hood was 1 "0i 1. 



Other references to P. scabriculus will be found in the paper cited above. The 

 species is common in S. India and is known from Kotri on the R. Indus and from 

 Pondicherry. It has also been recorded from Ceylon, from Saleyer and from Celebes. 



Genus LEANDER, Desmarest. 

 Leander styliferus (Milne Edwards). 



1837. Palaemon longirostris, Milne-Edwards, Hist. not. Crust., II, p. 394 (not P. longirostris, ibid., 



p. 392). 

 1840. Palaemon styliferus, Milne-Edwards, Hist. nat. Crust., Ill, p. 638 (nom.nov. for P. longirostris, 



loc. ctt. supra, p. 394). 

 1893. Leander longirostris , Henderson, Trans. Linn. Soc, Zool. (2), V, p. 439. 

 1902. Palaemon styliferus, Rathbun, Proc. U.S. Nat. Mus., XXVI, p. 51. 

 1908. Leander sp., de Man, Rec. Ind. Mus., II, p. 220, pi. xviii, fig. 3. 



The single specimen of this species found in the Chilka Lake is a non-ovigerous 

 female 62 mm. in total length : it agrees closely with Henderson's description. The 

 basal crest of the rostrum bears six teeth and there are two other dorsal teeth near 

 the apex; on the lower margin are eight teeth. The mandibular palp, as in the 

 genus Palaemon, is composed of three segments. 



The specimens recorded by de Man from Amoy in China l appear to be distinct 

 from this species. Apart from the differences noted by de Man in the proportions of 

 the branchiostegal and antennal spines (explained by Henderson as a clerical error in 

 the description), the short filament of the antennules is much longer in the Chinese 

 specimens and the second peraeopods considerably shorter. These legs in large 

 individuals from the Gangetic Delta reach beyond the antennal scale by the whole 

 length of the carpus and chela and, in smaller specimens, by at least the entire length 

 of the chela. The fingers in Indian examples are always much longer than the palm. 



1 De Man, Notes Leyden Mus., Ill, p. 141 (1881). 



