OCR Text |
Show 504 DR. J. E. GRAY ON SPONGES. [MaV 9- Fam. 11. CLIONIAD^E. Sponge living and making holes in shells, corals, and limestone. Skeleton composed of pin-shaped fusiform and cylindrical spicules fasciculated together. Sarcode granular. Order IV. ACANTHOSPONGIA. Spicules of more than one form or kind in the same sponge. Fam. 12. E U P L E C T E L L A D ^ E . Sponge tubular. Skeleton composed of longitudinal, transverse, and oblique bundles of spicules intersecting each other and forming a network. Sarcode mucilaginous, studded with many-rayed stellate spicules. Fam. 13. E S P E R I A D E E . Sponge massive. Skeleton composed of fusiform and linear spicules, interspersed with anchorate, bihamate, or birotulate spicules. Sarcode soft. Fam. 14. T E T H Y A D E E . Sponge subglobular or massive. Skeleton consisting of simple filiform spicules, with three prongs or three recurved points at the outer end, and with more or less globular many-rayed stellate spicules. Subsection 3. Sand Sponges (ARENOSPONGIJE). Sponge consisting of a subcircular disk of agglutinated sand or siliceous spicula, with a series of diverging filiform spicules on the circumference, and pencils of similar spicules on the mouth of the oscules on the upper surface of the disk. Order V. ARENOSPONGIA. Fam. 15. XENOSPONGIAD^E. Section II. CHLAMYDOSPORLE (Sponges with armed spores). by a thick ovisac, strengthened with siliceous spicules, the ovisac often at length becoming solid spheres formed of siliceous spicules radiating from a central point. Order VI. SPHCEROSPONGIA. Ovisac composed of closely packed fusiform spicules diverging from a centre, which, when the ova are emitted, extend internally and fill up the cavity, forming a nearly solid hall. Fam. 16. G E O D I A D ^ ; . Globose or subgiobose, fleshy; the ovisac forming a hard external coat. Fam. 17. P L A C O S P O N G I A D ^ E . Branched ; the ovisac forming a central axis and external plates, separated by sarcode and fasciculated spicules. Order VII. POTAMOSPONGIA. Ovisac coriaceous, strengthened with various-shaped spicules placed on, or in the substance of the ovisac. Fam. 18. SPONGILLAD^. |