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. Pedicellina ecliinata, Sars. (fig. 552). 



Fam. Loxosomidae. Long-stalked solitary animals. Loxosoma slngulare Kef., 

 L. ncapolitanii'ni 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. 



Sub-order 1. Lophopoda * (Phylactolaemata 



Allm.). 



Fresh-water Bryozoa (excepting the marine 

 Rhabdopleura} with horseshoe-shaped lophophore 

 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 Phylactolcemata 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- 

 552.-pKce7Kna niunicate with each other and give rise to 

 tchinata. Te, Tentacu- ramified, or more spongy massive stocks of 



lar crown ; O, mouth ; , , 



MD, alimentary canal always transparent, sometimes horny, sometimes 



.anus; softer (either leathery or gelatinous) consistency. 



Ov, ovary; G, gang- v & 



Hon. Statoblasts are very generally present. 



Fam. Cristatellidae. Free-moving colonies on the upper surface of which the 

 individual zooids are arranged in concentric circles. Cristatella mucedo Guv. 



Fam. Plumatellidae. Attached, massive or ramified colonies of fleshy or 

 coriaceous consistence. Loplwpus crystallinus Pall., Alcyonella fungosa Pall., 

 Plumatella repens L. (figs. 545, 553). 



G. J. Allman, " Monograph of Fresh-water Polyzoa." Ray Soc., 186. 



