. Zoology. Zoology. TEE BBAOHIOPODS. 45 the commonest objects of the sea-shore. They are minute, almost microscopic creatures, social, growing in communi- ties of cells, forming patches ^\\ on sea-weeds and stones (Fig. 46, Memhranipora solida). Cer- tain deep-water species grow in coral-like forms (Fig. 47, Myrio- zoum subgracile), while the chit- inous or horny Polyzoa are often mistaken for sea-weeds on the one hand, and Sertularian Hy- droids on the other. The animals inhabiting the microscopic cells are worm-like creatures (Fig. 48), with the di- gestive canal bent on itself and ending ne
. Zoology. Zoology. TEE BBAOHIOPODS. 45 the commonest objects of the sea-shore. They are minute, almost microscopic creatures, social, growing in communi- ties of cells, forming patches ^\\ on sea-weeds and stones (Fig. 46, Memhranipora solida). Cer- tain deep-water species grow in coral-like forms (Fig. 47, Myrio- zoum subgracile), while the chit- inous or horny Polyzoa are often mistaken for sea-weeds on the one hand, and Sertularian Hy- droids on the other. The animals inhabiting the microscopic cells are worm-like creatures (Fig. 48), with the di- gestive canal bent on itself and ending near the mouth, the lat- ter surrounded, as in the larger fresh-water species (Fig. 48, hr), with a horseshoe-shaped crown, or in the smaller marine forms F'o- <^of a Poiy- a circle of slender ciliated ten- tacles. The fresh-water forms {Phimatella, etc.) secrete no solid shell, and are either moss- like, or form large rounded masses of a jelly-like substance.*. zoon. A^Faliidictlla Ehrenbergii. B, PUilflatella frutico.';a. 6r. ten- tacular branchise of lophopliore; x^ oesophagus; v, stomach; r, in- testine: a, an\is; i, cell; x. poste- rior, x^, anterior cord, at the in- sertion of which into the body the generative products are devel- oped; f, testes; o, ovary; r*i, re- tractor muscles of the anterior portion of the cell; nir, principal retractor muscle. Class V.—Brachiopoda (Lamp Shells). General Characters of Brachiopods.—This group is named Brachiopoda, from the feet-like arms, fringed with tenta- cles, coiled up within the shell, and which correspond to the horseshoe-shaped crown of the Polyzoa and the crown of tentacles of the Sabella-like worms. From tlie fact that the animal secretes a true bivalved, solid sliell, though it is usually inequivalve, , the valves of different sizes, the * See the works of Allman, Hinks, Smitt, Saknsky, Sais, etc,. Please note that these images are extracted from scanned page images that may have been digitally enha
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectzoology, bookyear1897
