.VoL III, No. 1.] Notes on the Freshwater Fauna of India. 25 



[N.S,'] 



Among tlie gemmules of Spongilla carteH from Bhim Tal, 

 there are a few belonging to the genus EpJiydatta, These I have 

 little hesitation in identifying with Potts' Meyenia rohtista^ which, 

 as Potts himself says, may he a variety of EpJiydatta flttviatilis. 

 The original definition of the form is as follows : 



" Sponge massive, encrusting. Skeleton spicules subfusiform 



pointed, smooth. 



generally " monstrous 



Gemmules scarce, birotnlates of large size and 



irregularly shaped, shafts 



forai ; 



abounding in spiiies as long as rays of the I'otulfe, cylindrical of 

 conical. " . 



Potts' description of the gemmule spicules applies exactly 

 to those from Bhim Tal, except that among the latter thei'e are a 



The average length of the bii'otu- 



diameter of the rotulae 



average 



few which have smooth shafts. 



lates is 047 mm ; and the 

 0027 mm. In Californian specimens the equivalent measure- 

 ments are approximately 0*0237 mm. and 0*02 mm. It would 

 appear, therefore, that in Kumaon specimens the gemmule spicules 

 are slightly larger than in those fx*om America. A few of the 



jPjg. 7. Ephydatia rohusta. 

 Spicules of gemmules from Kamaon, x about 340. 



gemmules from the former locality had skeleton spicules adhering 

 to them wh;ch were " subfusiform, pointed, smooth. " Unfortu- 

 nately they were either bzx)ken or so small as to suggest that they 

 w^ere immature. The larger spicules of this class, however, must 

 have had when complete approximatelv the same actual and rela- 



tive dimensions as those 



rohmta. The gem- 



mules were spherical, with a single, deeply depressed aperture, 

 which was not provided with a foraminal tubule. There was 

 only one layer of gemmule spicules, ^vhich were quite vertical in 

 their cellular coating. They varied considerably in size. 



Ephydatia rohusta has only been recoi'ded hitherto fi^om 



"California ; so that its occuirence in Kumaon is of considerable 



interest. The material at my disposal is not sufficient for it to be 



possible to decide whether or no the Indian form should be regard- 



ed as a subspecies or variety of the Araej-ican. 



