334 A, FE. Verrill—The Bermuda Islands; Coral Reefs. 
when present, spirulas, spirastes, or asters; little or no spongin; no 
horny fibers; usually a compact cortex. Families, Suberitide, Poly- 
mastide, Clionide, Spirastrellide. 
Family, Chondrillide. 
Chondrilla nucula O. Schm. Figure 177. 
A soft, smooth sponge, with a tough cortex and a lubricous sur- 
face, forming small hemispherical masses, or thick convex, often 
irregular, incrusting forms, usually 1 to 3 inches in diameter, on 
rocks, dead corals, etc. Color various ; most frequently dark olive 
Figure 176.—Geodia gibberosa ; a, b, c, sterrasters in different stages of growth. 
Figure 177.—Chondrilla nucula ; euasters of different sizes. Drawn by A. H. V. 
green, varying to smoky brown or blackish, and to light green and 
yellowish green. Its texture is somewhat cartilaginous and elastic, 
without skeletal fibers. Minute, spinulated, spherical flesh-spicules 
(spherasters) are thickly scattered through the interior and more 
abundantly and partly of larger size in the cortex. 
Very common at low tide; occurs, also, throughout the West 
Indies. 
Family, Chalinide. (See p. 333.) 
Spinosella sororia (D. and M.) Dendy. Tube Sponge. Figures 141a, 179; 
Plate xxxvi, fig. 1 (21). 
Tuba sororia Duch. and Mich., Spong. mer. Caraibe, p. 46, pl. viii, fig. 1, 
1864. (The name Tuba was preoccupied.) Ss 
Spinosella sororia Dendy, Trans. Zool. Soc. London, vol. xii, p. 560, pl. 
lvili, fig. 7, pl. lix, fig. 1, 1890. 
Siphonochalina* papyracea Schmidt, Spong. atlant. Gebiet., p. 33, 1870, and 
var. Bermudensis. 
This species is common at moderate depths, especially in partially 
sheltered places. It generally forms a group of several upright tubes, 
1.5 to 2 inches in diameter, more or less united at the base, with the 
* The name Siphonochalina has been restricted by recent writers to the tube- 
sponges having a smooth, even surface. It seems doubtful if this be a good 
generic character. One species of that group occurs in Bermuda. 
