Sometimes these are very numerous, the whole interior being cavernous; again, the structure is more dense, with fewer large openings and more of the small ones between the tufts; again, the depressions are filled up so that the surface has fewer tufts. When living, the color is shining black. This is the best sponge found on the American coast, and although of coarser texture than the best Mediterranean sponges, it is more durable and quite as elastic. (Plate XL.) ^H. canaliculata^, variety ^flabellum^ (^Spongia graminea^, Hyatt). This is one of the species of sponges of the third commercial grade, which bear the trade-name of "grass-sponge." The shape is cone-like, with either a flat or a funnel-shaped top. The oscula are on the upper surface. The sides are fluted with deep furrows which contain the small incurrent apertures. GENUS ^Hircinia^ ^H. campana.^ The normal variety is vase-shaped, but the species varies greatly in form. Some varieties have branches. When living, its color is black. It is found at Key West in four to forty feet depth. (Plate XXXVIII.) II CŒLENTERATA (POLYPS) Phylum =CŒLENTERATA= Classes =HYDROZOA= (/Zoöphytes, small Jellyfishes, and a few Corals/) =SCYPHOZOA= (/Large Jellyfishes/) =ACTINOZOA= (/Sea-anemones and most of the Stony Corals/) =CTENOPHORA= (/Comb-jellies/) CŒLENTERATA The animals included in the phylum =Cœlenterata= were once all called /zoöphytes/, or animal plants, because of their resemblance to vegetable forms. The name /Cœlenterata/ is derived from two Greek words meaning "hollow" and "intestine," and it describes the anatomical structure of each member of the group. They are commonly known as polyps. In the simplest forms the parts which perform the different functions cannot be distinguished one from the other, and even in higher forms there is but little differentiation. Shakspere's description of old age applies to them: "Sans teeth, sans eyes, sans taste, sans everything." Nevertheless, this very low order of animals has, like the higher orders, such a diversity of form and habit as to require classification. Some of them are stationary, and of these some branch like plants; some move about by the aid of tentacles, some move by means of vibrating cilia, and others move by the contraction and expansion of the soft body.