Vol. ee No. 3.] Notes on the Freshwater Helina of India. 57 
N.S.] 
that eet in his monograph of the Freshwater Sponges of the 
world, recognized six varieties in addition to tro typical form. 
spicule, of which I have only seen twoexamples, as an abnormality. 
The gemmules are very distinctly of two sizes, the smaller 
ones being less numerous than the larger ones. They are ovcnrened 
directed outwards. They are not found in groups, and have n 
large air-cells. Dried pieces of the sponge bear a close external 
resemblance to Weltner’s? figure of part of a branch of Euspongilla 
lacustris from Germany ; but there is in the centre of each of sach 
cedtats pieces of the sponge. 
. lacustris has been recorded from brackish water in Europe 
and possibly i in Australia. The species is evidently adaptable, and 
its great fertilit a as regards gemmules, gives it every chance of a 
wide dispersa 
The common sponges in the Calcutta tanks are S. cartert_ and 
decipiens. The er propagates itself during the winter 
bodie 
either devoid of gemmules or contain only a a jae 
e life-history of these two forms di ffers also in other 
voapeelie The buds of S. carteri attach Sariipetvedh chiefly to water- 
plants such as Pistia stratiotes and Iimnanthemum and grow rapidly 
di 
into globular masses, which may be six or eight inches in di 
m These gradually weigh down the leaves or roots to which 
they adhere, and finally sink them in the The lower part of 
the sponge then dies, the cells probably migrating towards the 
upper part. S. decipiens, on the other hand, incrusts the lower 
part of the stems of reeds. bricks which have fallen into the water, 
and other sunk objects. Neither species is exposed to the air cs 
any great part of the year in Calcutta, as both are said by Carte 
to be exposed in Bom 
Both species shelter a number of Insect larve, some of which 
are generically identical with those found in the same position in 
Gegmany. minute Naidomorph worm is abundant in the 
| Proc. Acad. Nat. gine Philadelphia, 1887. 
2 Ent. Nachr. (Berlin) xx.,’No. 10, p. 150, fig. 7, 1 
3 Cf. M. and A. Weber, Zool. Ergeb. Niederland Ost- tad, Vol. 1, page 50,. 
