. Elementary text-book of zoology. Zoology. 78 BRYOZOA. a brood-pouch in which the testes and ovaries open and the embryos are developed. A pair of ciliated excretory canals is present. Fam. Pedicellinidae. Stocks with stolons, on which the long-stalked indi- viduals project. PedlcelUna ecJiinata, Sars. (fig. 552). Fam. Loxosomidse. Long-stalked solitary animals. Loxosoma singulars Kef., L. neapolitanum Kow. Order 2.—ECTOPROCTA. Bryozoa with anus opening outside the tentacular circlet, This group includes by far the greater number of the Bryozoa; their structure has been especially referred to
. Elementary text-book of zoology. Zoology. 78 BRYOZOA. a brood-pouch in which the testes and ovaries open and the embryos are developed. A pair of ciliated excretory canals is present. Fam. Pedicellinidae. Stocks with stolons, on which the long-stalked indi- viduals project. PedlcelUna ecJiinata, Sars. (fig. 552). Fam. Loxosomidse. Long-stalked solitary animals. Loxosoma singulars Kef., L. neapolitanum Kow. Order 2.—ECTOPROCTA. Bryozoa with anus opening outside the tentacular circlet, This group includes by far the greater number of the Bryozoa; their structure has been especially referred to in the precedent description of the class. The anus always opens outside the ring of tentacles, which are either arranged in a closed circle or on a two-armed horseshoe-shaped lophophore. Sab-order 1. Lophopoda * (Phylactolsemata Allm.). Fresh-water Bryozoa (excepting the marine Rhabdopleura) with horseshoe-shaped lopltophore and epistome. The Lophopoda are mainly distinguished by the bilateral arrangement of the numerous ten- tacles on the two-armed lophophore (fig. 553). There is always present above the mouth a moveable, tongue-shaped process, the epistome, whence the name Plujlactolcemata given by Allman to this sub-order. The zooids are usually of considerable * size, and, as opposed to the marine Bryozoa, they are all alike (, there is no polymorphism). The cells frequently com- FIG. 552. — Pediceiiina Hiunicate with each other and give rise to echinata. Te, Tentacu- ramified, or more spongy massive stocks of lav crown ; O, mouth ; . MO, alimentary canal always transparent, sometimes horny, sometimes (mesenteron);A,\ia; softer (either leathery or gelatinous) consistency. Or, ovary; G, gang- V J & lion. btatoblasts are very generally present. Fam. Cristatellidae. Free-moving colonies on the upper surface of which the individual zooids are arranged in concentric circles. Crlstatrllu mucedo Cuv. Fam. Plumatellidae, Attached, massive or ramified colonies of fl
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectzoology, bookyear1884
