OCR Text |
Show 050 DR. J. E. GRAY ON SPONGES. [May 9, Order VII. POTAMOSPONGIA. Ovisacs coriaceous, scattered in the tissue of the sponge, especially near the base. The cells coriaceous, with a permanent central cavity, strengthened externally with superficial spicules. Fam. SPONGILLAD^E. Sponge massive or branched. Skeleton formed of a network of spicula, more or less united together by horny matter; network symmetrical, four-sided. Living in fresh water.-Green. Spongilla, Lamk. A. s. Vert. ii. p. 98 ; Carter, Journ. Roy. Asiat. Soc. 1849, xii. p. 1. Ephydatia, Lamx.; Gray, Brit. Plants, i. p. 353. Tupha, Oken. Badagia, Buxbaum in Sprengel, Syst. Veg. iv. p. 374. I. The ovisacs thick, smooth, armed with birotate spicules, united by a central shaft, placed at right angles to and extending from the outer to the inner surface of the sac. 1. EPHYDATIA. Sponge-spicules fusiform, smooth. The disk of the ovisac-spicules entire or divided into lobes. * Disk of ovisac-spicules divided into lobes. 1. E P H Y D A T I A FLUVIATILIS, Bowerb. B. S. f. 217, 218 ; P. Z. S. 1863, p. 7, t. 38. f. 1. Hab. Europe. B.M. 2. EPHYDATIA MEYENII, Carter, Asiatic. Soc. Journ. xii. p. 4, t. 1. f. 1; Bowerb. B. S. f. 219; P. Z. S. 1863, p. 10, t. 38. f. 4. Hab. Bombay. B.M. ** Disk of ovisac-spicules entire. 3. EPHYDATIA LEIDYI. Spongilla leidyi, Bowerb. P. Z. S. 1863, t. 38. f. 2 (disk of ovisac-spicules entire, smooth). 4. EPHYDATIA CAPEWELLI. Spongilla capewelli, Bowerb. P. Z. S. 1863, t. 38. f. 2 (disk of spicules of ovisacs tubercular). 2. DOSILIA. Sponge-spicules of two forms:-1. Fusiform, smooth. 2. Cylindrical, nodulose; central nodules extending beyond the stellate, and some spherical stellates with a group of recurved hooks at the ends of |