SPONGES. 281 



the ova, which till then had floated on the surface of the 

 water, began to sink and attach themselves to the leaves 

 of the Anacharis and elsewhere. Latterly, they have all 

 subsided to the bottom of the jar, where they lie in com- 

 pany with a quantity of decayed vegetable matter, spawn 

 of the Limnceus, &c. They are of a light-brown colour, ovoid 

 in shape, longest diameter -0089, shortest diameter -0172. 

 The outer rim seems built up of cells of oblong shape, 

 but necessarily ill-defined, owing to their being observed 

 by light transmitted through two surfaces; the inner or 

 central portion also cellular, but from the convexity of 

 the object, more easy to determine as to its true nature, 

 formed of larger hexagonal-shaped cells. Seen by higher 

 power (J-in. obj. A. eye-piece 220 lin. diam.), these 

 central cells, besides being unmistakably hexagonal in 

 form, have each a distinct dark nucleus in the centre: 

 this, however, may be an optical fallacy, due to their 

 peculiar position on a curved surface. No movement yet 

 visible, April 25, 1857." 



In the journal of the Bombay branch of the Royal 

 Asiatic Society for 1849, Surgeon H. J. Carter gives a 

 very accurate account of fresh-water sponges found in the 

 water tanks of Bombay. Of five species that he discovered, 

 one was the Spongilla friabilis, the others he named Sp. 

 cinerea, Sp. alba, Sp. meyeni, Sp. plumosa. 



Spongilla cinerea is stated to present on its surface a 

 dark, rusty, copper colour, lighter towards the interior, 

 and purplish under water. It throws up no processes, but 

 extends horizontally in circular patches, over surfaces two 

 or three feet in circumference, or accumulates on. small 

 objects; and is seldom more than half an inch in thickness. 

 It is found on the sides of fresh-water tanks, on rocks, 

 stones, or gravel. Seed-like bodies spheroidal, about l-63d 

 of an inch in diameter, presenting rough points externally. 

 Spicula of two kinds, large and small; large spicula, 

 slightly curved, smooth, pointed at both ends, about 

 l-67th of an inch in length; small spicula, slightly 

 curved, thickly spiniferous, about l-380th of an inch in 

 length. 



Spongilla friabilis. Growing in circumscribed masses, 

 on fixed bodies, or enveloping floating objects; seldom 



