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Notes on the Freshwater Fauna of India* No* IX. 

 Descriptions of new Freshwater Sponges from Calcutta^ 

 with a record of two known species from the Himalayas 

 and a list. of the Indian forms. 



By N. Annandale, D.Sc. 



All the forms described below have been found within the 

 last few months in the Museum tank, Calcutta, Spmigilla carteri^ 

 Bowerbank, and S. decipiens, Weber, also occur in this tank, 



favourable 



brates. Indeed, I know of no habitat in the neighbourhood of 

 Calcutta so favourable. I hope to publish later an account of 

 observations on the biolo 

 Sponges, 



gy 



of several of these Freshwater 



Spongilla proliferbns, sp. uov. (Fig, 1.) 

 Diagnosis. 



Sponge encrusting, thin, surrounding or spreading over the 

 roots, leaves and stems of water-plants, and often matting them 

 together, leaf- green (when exposed to light), rai^ely extending for 

 more than about 2 square inches ; the sui^face frequently covered 

 with minute, rounded branches not more than 3 mm. 



which separate as buds from the parent at an early stage. 



long, 

 Der- 



mal membrane delicate, often widely separated from the underly- 

 ing parts and forming conspicuous, flask-shaped collars round the 

 oscula, which are congregated ; pores few and inconspicuous ; deep 

 channels covered only by the dermal membrane frequently occur 

 on the surface. Skeleton spicules slender, smooth amphioxi, 

 generally crescentic but sometimes almost straight, 25 — 30 times 

 as long as their greatest transverse diameter, gradually pointed. 

 They are loosely bound together' in strands which form an irre- 

 gularly reticulated skeleton, and on the surface project vertically 

 upwards through the dermal membrane. Flesh spicules short, 

 slender, cylindrical amphioxi or, more commonly, amphistrongyli, 

 which are profusely and evenly microspined, the spines being 

 straight and conical; the spicules about 9 times as long as broad. 

 Gemmule spicules often identical with the flesh spicules, but 

 less frequently amphioxous and on an average stouter and shorter. 

 Gemmules separate, subspherical or spherical, often slightly 

 flattened on one face ; the single aperture lateral ; the chitinous 

 coating rather stout, surrounded by a layer of microcell substance 

 of variable thickness in which the gemmule spicules are arranged 

 tangentially and vertically, crossing one another irregularly ; 

 the apertui'e provided with a stoiit foraminal tubule, which is 



