REPRODUCTION OF CAMPANULARID.E AND SERTULARID^E. 541 



digestion, however, a portion finds its way down into the tubular 

 Stem, for the nourishment of the general fabric ; and very much 

 the same kind of circulatory movement can be seen in Campanu- 

 laria as in Tubularia, the circulation being most vigorous in the 

 neighbourhood of growing parts. It is from the soft flesh (/) 

 contained in the Stem and branches, that new Polype-buds (b) are 

 evolved ; these carry before them (so to speak) a portion of the 

 horny integument, which at first completely invests the bud ; 

 but as the latter acquires the organization of a Polype, the 

 case thins-away at its most prominent part, and an opening is 

 formed through which the young polype protrudes itself. 



418. The origin of the bodies commonly but erroneously desig- 

 nated 'Ovarial Capsules' (e), is exactly similar ; but their desti- 

 nation is very different. Within them are evolved, by a budding 

 process, the Generative organs of the Zoophyte : and these in the 

 Campamdaridce may either develope themselves into the form of 

 independent Medusoids, which completely detach themselves from 

 the stock that bore them, make their way out of the capsule, and 

 swim -forth freely, to mature their sexual products (some develop- 

 ing Spermatozoa, and others Ova) and give origin to a new genera- 

 tion of Polypes ; or, in cases in which the Medusan structure is 

 less distinctly pronounced, may not completely detach themselves, 

 but (like the Flower-buds of a Plant) expand one after another at 

 the mouth of the capsule, withering and dropping-off after they 

 have matured their generative products. In the Sertularidce, on 

 the other hand, the Medusan conformation is altogether wanting ; 

 but the so-called Ovarial Capsules (Fig. 277), which have been 

 shown by Prof. Ed. Forbes to be really metamorphosed branches, 

 develope in their interior certain bodies which were formerly sup- 

 posed to be Ova, but which are now known to be Medusoids reduced 

 to their most rudimentary condition. "Within these are developed, — 

 in separate Capsules, sometimes perhaps on distinct Polyparies, — 

 Spermatozoa and Ova ; and the latter are fertilized by the entrance 

 of the former whilst still contained within their capsules. The 

 fertilized Ova, whether produced in free or in attached Medusoids, 

 develope themselves in the first instance into ciliated ' Oemmules,' 

 which soon evolve themselves into true Polypes, from every one of 

 which a new Composite fabric may spring. 



419. There are few parts of our Coasts which will not supply 

 some or other of the beautiful and interesting forms of Zoophytic 

 life which have been thus briefly noticed, without any more trouble 

 in searching for them than that of examining the surfaces of rocks, 

 stones, sea-weeds, and dead shells between the tide-marks. Many 

 of them habitually live in that situation; and others are frequently 

 cast-up by the waves from the deeper waters, especially after a 

 storm. Many kinds, however, can only be obtained by means of 

 the Dredge. For observing them during their living state, no 

 means is so convenient as the Zoophyte Trough (§ 98), devised for 



