464 



ZOOPHYTES. 



not only affords an investment to the stem, but forms cups or 

 cells for the protection of the polypes, as well as capsules for 

 that of the reproductive bodies. In the (Jampamdaridoe, the 

 polype-cells are campanulate or bell-shaped, and are borne at the 

 extremities of ringed stalks (Fig. 223, c) ; in the Sertularidce, on 

 the other hand, the polype-cells lie along the stem and branches, 

 attached either to one side only, or to both sides (Fig. 224). In 

 both, the general structure of the individual polypes (Fig. 223, d) 



closely corresponds with 

 Fio- 223. that of the Hydra ; and 



the mode in which they 

 obtain their food is essen- 

 tially the same. Of the 

 products of digestion, 

 however, a portion finds 

 its way down into the tu- 

 bular stem, for the nour- 

 ishment of the general 

 fabric; and very much the 

 same kind of circulatory 

 movement can be seen in 

 Campanularia, as in Tu- 

 bularia, the circulation be- 

 ing most vigorous in the 

 neighborhood of growing 

 parts. It is from the soft 

 flesh (/) contained ia the 

 stem and branches, ■ that 

 new polype-buds (h) are 

 evolved; these carry be- 

 fore them (so to speak) a 

 portion of the horny in- 

 tegument, which at first 

 completely invests the 

 bud ; but as the latter 

 acquires the organization 

 of a polype, the case thins 

 away at its most promi- 

 nent part and an opening 

 ^ , . , ,. , , is formed, through which 



Cawipawutana^e^aiinojfa;— A, upper part of the stem and ji -.^ 



branches, of the natural size; B, a small portion enlarged, ^'^^ JOUng polypC pPO- 



showing tlio structure of the animal; o, terminal branch trudes itself. The Oriffiu 



bearing polypes; b, polype-bud partially developed; c, ^f ^\^ \^r,A\ac, 1 



horny cell, containing the expanded polype, d; e, ovarian UOUICS COmmOUiy 



capsule, containing medusiform gemmffi in various slages DUt errOUCOUsly dcsio"- 



of development ;/, fleshy substance extending through the nafprl "nvsn-ian r^a■na■,^^ c3 ' 



stem and branches, and connecting the different polype- ! f" ."^ OVariail CapSUlCS 



cells and ovarian capsules; ^, annular constrictio]is at the (^/> IS CXactly Similar ; but 



base of the branches. their destination is very 



, , , , ^^. different. Within them 



are evolved, by a buddmg process, the generative organs of the 



