Skeleton diffuse, consisting of very fine radiating fibres, which are crossed at wide and irregular intervals by still finer transverse ones; very little chitinoid substance present.
Spicules. Skeleton-spicules smooth, slender, sharply pointed at both ends, nearly straight. No true flesh-spicules. Gemmule-spicules straight or nearly so, cylindrical, or constricted in the middle, obscurely pointed or blunt, clothed with short, sharp, straight spines, which are very numerous but not markedly longer at the two ends; these spicules frequently found free in the parenchyma.
Gemmules numerous, small, free, spherical, yellow, with a well-developed granular coat (in which the spicules are arranged almost horizontally) and external to it a fine membrane which in preserved specimens becomes puckered owing to unequal contraction; each gemmule with a single aperture provided with a straight, rather wide, but very delicate foraminal tubule.
Measurements of Spicules and Gemmules.
| Length of skeleton-spicule | 0.313 mm. |
| Breadth of skeleton-spicule | 0.012 mm. |
| Length of gemmule-spicule | 0.062 mm. |
| Breadth of gemmule-spicule | 0.004 mm. |
| Diameter of gemmule | 0.313-0.365 mm. |
This sponge in its general structure bears a very close resemblance to Spongilla crateriformis.
Type in the collection of the Indian Museum.
Habitat. Growing on weeds at the edge of the Sur Lake, Orissa, October 1908. Only one specimen was taken, together with many examples of S. lacustris subsp. reticulata, S. carteri and S. crassissima.
7. Spongilla crateriformis* (Potts).
Meyenia crateriforma, Potts, P. Ac. Philad. 1882, p. 12. Meyenia crateriformis, id., ibid. 1887, p. 228, pl. v, fig. 6, pl. x, fig. 5. ? Ephydatia crateriformis, Hanitsch, Nature, ii, p. 511 (1895). Ephydatia crateriformis, Weltner, Arch. Naturg. lxi (i), pp. 122, 134 (1895). ? Ephydatia crateriformis, Hanitsch, Irish Natural. iv, p. 125, pl. iv, fig. 5 (1895). Ephydatia indica, Annandale, J. Asiat. Soc. Bengal, 1907, p. 20 (figures poor). Ephydatia indica, id., Rec. Ind. Mus. i, pp. 272, 279, 388, 391 (1907). Ephydatia crateriformis, Scharff, European Animals, p. 34 (1907). Ephydatia crateriformis, Annandale, P. U.S. Mus. xxxvii, p. 402, fig. 1 (1909).