MARYLAND GEOLOGICAL SURVEY 213 



COELENTERATA. 

 class PORIFERA. 



subclass SILICISPONGIAE. 

 order H ADROMERINA. 



Suborder CLAVULINA. 

 Family CLIONIDAE. 



Genus CLIONA Grant. 



Cliona sulphurea (Desor) Verrill. 



Plate LXVI, Figs. 1-6. 



Spongia sulphurea Desor, 1848, Proc. Boston Soc. Nat. Hist, vol. iii, p. 68. 

 Gliona sulphurea Verrill, 1873, Invert. Animals Vineyard Sound, Rept. 



Com. Fish and Fisheries, pp. 421, 744. 

 Gliona sulphurea Verrill, 1878, Amer. Jour. Sci., 3rd ser., vol. xvi, p. 406. 



Description. — " A bright sulphur-yellow species, growing into hemi- 

 spherical or irregular, massive forms, of firm texture, the surface cov- 

 ered with scattered, low, wart-like, soft prominences, about an eighth of 

 an inch in diameter, which contract when the sponge is dried, leaving 

 shallow pits. The sponge commences as a boring species, on various dead 

 shells, and as it grows it penetrates the shells in every direction, forming 

 irregular holes and galleries, which continue to grow larger as more and 

 more of the substance of the shell is absorbed, until the shells are reduced 

 to a completely honey-combed, brittle mass, or a mere skeleton; finally 

 the sponge begins to protrude from the surface, and grows up into mam- 

 milliform masses, or small, rounded crusts, which continue to grow and 

 spread in every direction, until finally they may form masses six or 

 eight inches in diameter, with the base spreading over and enveloping 

 various dead shells, pebbles, and the coral, Astrangia Dance, though it 

 often happens that the living specimens of the latter grow upon the 

 sponge. Owing to the remarkable boring habits of this and other allied 

 sponges, they are very important in the economy of the sea, for they are 

 the principal agents in the disintegration and decay of the shells that 

 accumulate over the bottoms, thus performing the same function in the 



