STOMATOPODA. 



By Stanley Kemp. 



Two species and one variety of Stomatopoda have been found in the Chilka Lake, 

 but the only one that is abundant is Squilla scorpio var. Immaculata, a form also 

 common in brackish water in the Gangetic delta. The occurrence both of S. scorpio 

 and its variety immaculata is of some interest, for the two had not hitherto been 

 found together. No specimens intermediate in character were observed, and it is 

 possible that the two forms should more properly be recognised as distinct species. 

 A knowledge of the early stages might throw light on this point ; but all the larvae 

 found in the lake are of one type and, if a difference exists in the structure of the 

 Alima, they belong presumably to the more abundant var. immaculata. The third 

 form, Squilla interrupta , seems to be merely a casual visitor to the lake-system, in 

 which only one example has been found. This species and the typical form of 5. 

 scorpio have a wide Indo-pacific distribution, while the variety immaculata is known 

 from an area extending from the mouth of the Indus to the coast of Burma. 



Family SQUILXIDAE. 

 Genus SQUILLA, Fabricius. 

 Squilla scorpio, Latreille. 

 1913. Squilla scorpio, Kemp, Mem. Ind. Mus., IV, p. 42, pi. ii, fig. 30. 



The typical form of this species is very scarce in the Chilka Lake ; it is represented 

 in our collection by two males and eight females, the largest 67 mm. in length. 

 The black patch on the lateral process of the fifth thoracic somite is conspicuous in 

 all the specimens, even in the smallest, an individual only 21 mm. long. 



Squilla scorpio was found both in the main area and in the outer channel of the 

 lake in water varying in specific gravity from i - ooo to 1-0265. It is known to be 

 distributed over an area extending from the east coast of India to N". Australia and 

 Celebes and has, apparently, hitherto been obtained only in the sea. 



var. immaculata, Kemp. 



1913. Squilla scorpio var. immaculata, Kemp, Mem. Ind. Mus., IV, p. 45, pi. ii, fig. 31. 



Squilla scorpio var. immaculata is one of the commonest Crustaceans in the 

 main area of the lake, occurring on a muddy bottom at all seasons of the year. It 

 was also obtained on similar ground at the inner end of the outer channel and is able 

 to exist, and apparently to breed also, in water varying in specific gravity from i - ooo 

 to 1-0265. 



