702 Memoirs of the Indian Museum. [Vol,. V, 1922.] 



description and figures of Stiliger mariae (M. & M.), 1 but the stylet of the penis is 

 extremely short, slender and minute. The cup-like structure of the tip is with- 

 drawn in a strongly muscular sheath. The alimentary system is also of the same 

 type as in S. mariae and the radula is closely similar. The hepatic diverticula in 

 the cerata (fig. 2) are not much coiled and bear only a few short branches. 



S. pica differs from most species of Stiliger in its slender cerata, but otherwise 

 seems to be a typical member of the genus. The only other species described from 

 brackish water is 5. tentaculatus Eliot. This peculiar form differs greatly from other 

 species in having well-developed oral tentacles and also tentacle-like processes at 

 the antero-dorsal angles of the foot. 



The only specimen of S. pica we have seen was found in the latter part of June, 

 1920, in a small aquarium containing stones from the end of the landing- stage at 

 Barkuda in the Chilka Lake. These stones were covered with both green and dark 

 purple algae and it was not until they had been under observation for some days 

 that the mollusc was observed, owing largely to the chance that it had strayed into 

 a mass of green filamentous algae in which its dark colouration rendered it very 

 conspicuous. 



The number of Nudibranch molluscs known from brackish water in the Oriental 

 Region is still small, but is increasing with our knowledge of the estuarine faunas and 

 of those of maritime lakes. The following list may be of interest : — 



Tribe Cladohepatica. 

 Family Aeolididae. 



Cuthona annandalei Eliot ; Gangetic Delta. Rec. Ind. Mus. V, pp. 248, 249, pi. 



xix (1910). 

 Cuthona henrici Eliot ; Chilka Lake, east coast of India. Mem. Ind. Mus. V, p. 

 377, fig. 1 (1916). 



Family Hermaeidae. 



Stiliger tentaculata Eliot; Talé Sap, Gulf of Siam. Mem. As. Soc. Bengal VI, 



pp. 179-182, figs. 1, 2 (1917). 

 Stiliger pica, sp. nov., Chilka Lake. 



Family Efysiidae. 



Elysia chilkensis Eliot; Chilka Lake. Mem. Ind, Mus. V, p. 378 (1916). 



1 Semper's Reisen in Phillipinen, Wiss. Res. Th. II, Cd. II, pp. 139-144, pi. xxvi, figs. 1-17 (1870- 

 1875). See also Eliot, Brit. Nud. Moll, pt. VIII (suppl. pp. 136-137). According to Eliot, the species 

 should be known as S. bellulus M. & M. 



