SPONGES 107 



GENUS Microciona 



M. prolifera. When young this species forms bright-red incrustations 

 over shells and stones ; later it rises into irregular lobes and tubular prom- 

 inences. When fully developed it is profusely branched in a forking 

 manner. The branches are more or less flattened, and often are palmate 

 at the ends. It grows in clusters six inches in diameter, of a dark 

 orange-red color. When dry it is grayish-brown, brittle, and bristly. 

 It is found from Cape Cod to South Carolina, and is abundant in Long 

 Island Sound. (Plate XXXIX.) 



GENUS Tedania 



Irregular, uneven, pale-yellow masses spreading over seaweeds ; 

 oscula scattered irregularly over the surface ; texture close. 



GENUS Halichondria 



H. panicea, cmmb-of -bread sponge. It resembles the crumb of 

 bread, and is found cast up on all beaches. (Plate XXXVIII. ) 



GENUS Clialinopsilla 



C. oculatct, the finger-sponge. Stem stout, more or less flattened, 

 dividing at the upper end into branches which vary in form and thickness, 

 being finger-like or more or less compressed lobes ; oscula scattered over 

 the smooth, undulating surface ; texture rather hard, but delicate ; color, 

 when living, dull orange-red; when the animal matter is removed, 

 white. The species is found in shallow and deep water from New York 

 to Labrador. Common in Massachusetts Bay. (Plate XXXIX.) 



arbuscula. Profusely branched in a forking manner from close 

 to the base ; branches slender ; clusters six to eight inches high and 

 about the same in breadth ; color buff or gray when living, yellowish- 

 white when free from animal matter ; texture finer and more delicate than 

 that of C. oculata. It is found in shallow water from Cape Cod to North 

 Carolina, and is abundant in Long Island Sound. (Plate XXXIX.) 



GENUS Euspongia 



E. offlcinalis. This is one of the commercial sponges and is known 

 as the " glove-sponge." It is the one of least marketable value, having 

 inferior elasticity and becoming brittle with age ; yet a Mediterranean 

 sponge of the same species, variety adriatica, is of the finest quality and 

 greatest value. This singular fact demonstrates that the quality of 

 sponges depends largely upon physical conditions. E. officinalis has 

 an average height of five to six inches. It grows on rocky bottoms 

 in shallow water on the east coast of Florida. This species has a num- 

 ber of varieties of various forms; some are dome-shaped, others tubular, 

 rotund, flabellate, etc. The surface is covered with fine tufts and is 

 generally free from ridges. On the sides are numerous small apertures, 



