Text-book of comparative anatomy . 2. Ectoprocta. Anal opening outside of the tentacle carrier. Tentacle carrier not body naked, posterior body shelled. Without stalk. Anterior body soenveloped in a fold of the posterior body as to be either temporarily or permanentlysurrounded by a sheath (tentacle sheath) out of which it can be protruded. Bodycavity tolerably spacious. Shell often calcareous. Colonial. Phyladolccmata. Tentacle carrier horseshoe-shaped. In-habit fresh water. Cristatclla, Alcy-onclla, Frcdericella, Lophopus (), Plumatella (Fig. 139, p. 208).Gymnolcemat
Text-book of comparative anatomy . 2. Ectoprocta. Anal opening outside of the tentacle carrier. Tentacle carrier not body naked, posterior body shelled. Without stalk. Anterior body soenveloped in a fold of the posterior body as to be either temporarily or permanentlysurrounded by a sheath (tentacle sheath) out of which it can be protruded. Bodycavity tolerably spacious. Shell often calcareous. Colonial. Phyladolccmata. Tentacle carrier horseshoe-shaped. In-habit fresh water. Cristatclla, Alcy-onclla, Frcdericella, Lophopus (), Plumatella (Fig. 139, p. 208).Gymnolcemata. Tentacle-earner circu-lar. Livejwith the exception of Palu-dicclla, in the sea. Cellepora, Eschara,Bugula, Flustra, Alcyonidium, Hor-ncra, etc. Sub-Order 3. Entoprocta. Anal opening inside the tentaclecarrier. A tentacle sheath stalked. With one pair of neph-ridia. Body cavity reduced. Pedi-cellina, colonial. Loxosoma, livingsingly. Marine. Order 4. Brachiopoda (Fig. 178, p. 269).ft The dorsal and the ventral body. pr- FIG. 122.—Anterior body of Lophopus (afterAllman), from the right side, t, Tentacles cut offnear the base; o, mouth; ep, epistome; st, fore-gut ; ga, ganglion; an, anus; pr, hind-gut. Thefree ends of the tentacle-carrier are cut off. walls form a fold directed to the front,so that the body is covered by dorsaland ventral mantle folds, which maycoalesce behind and at the sides. The mantle folds secrete calcareous, and occasionallyhorny shell valves, a dorsal and a ventral. The ventral valve is generally the moreconcave. At the sides of the mouth are inserted the two long oral arms set withlateral cirri; these arms lie spirally rolled up in the mantle cavity, which isformed by the mantle folds, and are often supported by a special calcareous skeletonunited to the dorsal valve. Anus wanting, or lies asymmetrically and anteriorly,to the right, near the mouth. In Crania only it lies quite behind, in the dorsalmiddle line. Central nervous system is an
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectanatomycomparative
