SPONGES, HYDROZOA AND POLYZOA OF THE 



INLE LAKE. 



By N. Annandale, D.Sc, F.A.S.B., Director, 

 Zoological Surrey of India. 



With Plate XXI. 



The Porifera, Hydrozoa and Polyzoa of the Inle Lake belon<2; without 

 exception to species also found in India proper and only in one instance, 

 that of the cosmopolitan Ephydatia fluviatilis, can diiTerences be found 

 even sufficiently great for varietal separation. The most remarkable 

 feature of the fauna so far as these groups are concerned lies in its defi- 

 ciencies, above all in the apparently complete absence of Phylactolae- 

 matous Polyzoa. The three groups, therefore, cast no light on the 

 origin of the fauna and are of less interest than was perhaps anticipated. 



PORIFERA. 



Only three species of sponges, all of them cosmopolitan as species, 

 are represented in our collection. They are Spongilla lacustris, Spongilla 

 jragilis and Efhydatia fluviatilis, perhaps the three commonest species 

 in the Holarctic Zone. The first two, however, occur as varieties only 

 known from the Oriental Region, while the last differs somewhat both 

 from the forma typica and from the Indian race Jiimalayensis. I have, 

 therefore, recognized it as a new variety under the name intha {i.e., 

 literally, " son of the lake " in Burmese). 



Spongilla lacustris var. proliJerens, Annandale. 



1911. S'poncjilla jjroUferens, Annandale, Fmtn. Brit. Ind., Freshir. Spongzs, etc., 



p. 72, fig. 9. 

 1915. Spoiujilla lacustris var. proliferens, id., Mem. Ind. M us. V, p. 28. 



This sponge was found in abundance in February and March in a 

 pond a few miles east of the town of Yawnghwe. Specimens were also 

 taken near the western shore of the Inle Lake and in rice-fields west of 

 that shore. They agree with specimens from Calcutta and have the 

 characteristic buds well developed. Gemmules were also present in 

 most specimens. 



This form of the cosmopolitan Spongilla lacustris has been found 

 at many places in the Indo-Gangetic Plain, Peninsular India and 

 Burma. 



Spongilla fragilis var. calcuttana, Annandale. 

 (Plate XXI, fig. 1). 



1911. Annandale, op. cil., p. 96, fig. 15. 



Dried specimens of this sponge were found coating the house-posts 

 of the monastery guest-house at Thale-u on the eastern side of the lake. 



