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 (i.e., 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,a.n\ia; so fter (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 fleshy or 

 coriaceous consistence. Loplwpus cryxt all inns Pall., Alcyonclla fungosa Pall., 

 Plumatclla rcpens L. (figs. 545, 553). 



* G. J. Allman, " Monograph of Fresh-water Polyzoa." Ray Soc., 1856. 



