164 THE POPULAR SCIENCE MONTHLY. 



visitors often pick up tufts on the beach, and press them for sea-weeds. 

 They are really the skeleton structures of a remarkable zoophyte, the 

 Sertularia. We have an elegant species that grows upon the oyster, 

 named Sertularia argentea, because it is often so white and glittering 

 that it looks almost like silver. These I have found sometimes sixteen 

 inches high, making the most exquisite gossamer-tree. But it is no 

 tree or plant proper. Their substance is chiefly lime. They might 

 well be called sea-ferns. When magnified, living specimens show 

 what might be mistaken for little buds. If the microscopist is both 

 skillful and patient, he will see a little starry object like a flower push 

 itself out of one of these buds, which is really its case in which it lives. 

 It may be seen waving its little life-petals about, catching food. I 

 have not forgotten the delight experienced when I found out this fact 

 for myself. Let the reader dwell a moment on Fig. 6. The Sertularia 

 buoys up the oysters, as does the red sponge. And one may readily 

 conceive how the animalcules must swarm in these gossamer-like for- 

 ests or groves, so that not only the zooids but the oyster also enjoys 

 the richness of the fishing-ground. 



Everybody, that has seen any dredging in Long Island Sound, 

 knows that lumps of matter made up entirely of small calcareous 

 tubes abound there. These tubes are often found adhering to the 

 oyster ; in fact, these animals build them on the oyster's shell. Its 

 name is Sabellaria vulgaris, so named by Prof. Verrill. The construct- 

 or and occupant is a worm, but, for all that, a creature of surpassing 

 beauty. In company with this, another little being builds a tubular 

 home on the oyster. It is a small serpula or serpent-shell, and is 

 called by Verrill, Serpula dianthus, the pink serpula, because, when 

 the little dweller therein projects its tiny florets, in form and color 

 they suggest the pink of our gardens. But there is projected by the 

 side of that pretty little pink, a curious, funnel-shaped process, that 

 looks like the tiniest kind of a trumpet. We have watched those 

 pretty creatures with their floral heads out fishing. Let the slightest 

 jar be given, and the little thing takes alarm and instantly withdraws 

 into its stony tube : first the floral head disappears, then the trumpet- 

 like structure is drawn in, which actually plugs np the entrance. All 

 this will be understood from Fig. 7, which shows a serpula. The spir- 

 orbis here figured is really a serpula, a tube coiled into a spiral. I 

 have never seen the spirorbis growing on the oyster-shell, but have 

 taken it from sea-weeds and Bryozoa thence obtained. 



This natural plug, or stopper, is not without a smack of drollery. 

 At least it has always impressed me as having in it a taste of the in- 

 tensely utilitarian. And this reminds me that, in all their beauty, there 

 is also a savor of the comical in the Bryozoa. Please to look at 

 that Avicularlum in Fig. 5, 3. Is it not like the head of an eyeless 

 bird ? To see this "bird-head process " at work, one feels irresistibly 

 that it is a real zooid, an individual among the Bryozoa, and Huxley 



