OCR Text |
Show 540 DR. j. E. GRAY O N SPONGES. [May 9, ORINA ANGULATA. Halichondria angulata, Bowerb. ib. ii. p. 233. VI. Defensive spicules regular, birotulate, with many rays end, free in sarcode. 31. CARTERIA. Sponge massive, irregularly reticulated, shallow, formed of abundant agglutinated filiform needle-like spicules, with four- and six-rayed stellate, cruciform, and birotulate spicules. Hyalonema, part., Bowerb.; Schultze ; Brandt (not Gray). CARTERIA JAPONICA. « Hyalonema mirabilis, Bowerb. B. S. i. p. 237, f. 60-65 ; p. 276, f. 294, 295 ; Schultze, t. 3 & 4 (not Gray). B.M. Hab. Japan. Bowerbank's figures (Br. Sp. 153-157) represent the spicules of the corium that surround the filaments of Hyalonema mirabilis, Gray, and have nothing to do with the smooth stellate or radiate spicula of this sponge. They have been called Spongia octancyrce, Brandt, Hyal. p. 14; Spongia spinicruces, Brandt, Hyal. p. 23, t. 3. f. 15, 16. They are also figured in Schultze's 'Hyalonema,' t. 3. f. 9-14. Fam. 3. TETHYADEE. Sponge massive, suborbicular or subramose, fleshy. Skeleton consisting of simple fusiform and of fusiform spicules with three prongs or three diverging hooks at the distal or outer extremity, and with more or less globular many-rayed stellate spicules, or of either of the two kinds. The stellate spicules are composed of few or many radii, emanating from a centre in all directions. Their simplest form is when the bases of the radii all proceed from a common point; in others the radii spring separately and distinctly from a common central spherical or oval base.-Bowerb. Phil. Trans. 1858, p. 307, 309. Dr. Bowerbank calls the elongate spicules which are peculiar to Geodiadce and Tethyadee connecting spicula. These spicula have a long, stout, cylindrical, or attenuated shaft, terminating either acutely or hemispherically at the base ; while the apex is divided into three stout equiangular radii, which assume in different species a considerable variety as regards form and direction. The triradiate apices are usually cemented firmly to the inner surface of the crus-tated coat of the sponge; while the stout and elongated shaft is intermingled with and firmly cemented by keratode to the general mass of the skeleton. The triradiate apices also serve to construct areas in which are situated the proximal orifices of the intermarginal cavities, which are imbedded in the crustated surface of the sponge.- Bowerb. Phil. Trans. 1858, p. 289. |