Elementary text-book of zoology (1884) Elementary text-book of zoology elementarytextbo0201clau Year: 1884 BRYOZOA. 1-0 I • > into two lobes so as to have a horse-shoe shape (Lop/iopoda, fig. 54.'),. and its margins are produced into a number of richly ciliated ten- tacles. The tentacles are simply hollow processes of the body wall; they are provided with longitudinal muscles, and their cavity com- municates with the body cavity, from which they are filled with blood. They serve both for procuring food (setting up by means of their cilia whirlpools in the water) and for respiration. ,- The
Elementary text-book of zoology (1884) Elementary text-book of zoology elementarytextbo0201clau Year: 1884 BRYOZOA. 1-0 I • > into two lobes so as to have a horse-shoe shape (Lop/iopoda, fig. 54.'),. and its margins are produced into a number of richly ciliated ten- tacles. The tentacles are simply hollow processes of the body wall; they are provided with longitudinal muscles, and their cavity com- municates with the body cavity, from which they are filled with blood. They serve both for procuring food (setting up by means of their cilia whirlpools in the water) and for respiration. ,- The digestive organs lie freely in the body cavity, and are attached to the integument by the Mj-called funiculus and by bundles of muscles. The body and tentacular apparatus has been in- correctly regarded as a kind of individual, and opposed to the cell or Cystid, in which it is placed, as the Polypid. The mouth is placed in the centre of the circular or horse-shoe shaped lophopore, and a moveable epiglottis-like process, known as the epistome, often projects over it. The alimentary canal is bent on itself, and consists of (1) an elongated ciliated oesophagus often dilated to a muscular pharynx ; (2) a spacious stomach, with a blind backward prolongation, the hind end of which is attached to the body-wall by a cord (funiculus), and (3) a narrow intestine, which is bent up nearly parallel with the pharynx and is directed forwards. The intestine opens by the dorsally-p laced anus, near but usually outside the buccal disc (Ectoprocta, tig. 545). In a few forms the anus is within the circle of tentacles (Endo- in-octa), Pedicellina and Loxosoma (fig. 546). ' FIG. 546.— /'.'' Heart and vascular system are absent. The ,,•!,,,,„*•,. ?-,, tentaou- blood fills the whole body cavity, through which ^r crown; 0, mouth; MI),alimentary canal; it is circulated chiefly by the cilia of the body- A, anus; G,ganglion; wall. The whole surface of the anterior protrusible part of the
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