ASSUMPTION OF THE POLYPE-FORM. 358 



gemmules (fig. 9) seem to escape from the walls of the 

 ovaries, working their way out at the sides. They 

 drop down on the bottom of the vessel, where they 

 move about slowly for a while, to no great ex-tent, by 

 means of their vibratile cilia. 



All through September, as this species was very 

 numerous in the harbour and in the neighbouring 

 coves, I procured great numbers of them, most of 

 which I placed in a deep cylindrical glass vessel, — 

 the chimney of a lamp, in fact, with a plate of glass 

 cemented across one end for a bottom. By examining 

 this bottom-plate from beneath with a lens, I found 

 early in September that a good many of the gemmules 

 had affixed themselves to it, and were changing their 

 form. By watching them, I ascertained the following 

 facts. The gemmule, having adhered to the glass, 

 grows out into a lengthened form, variously knobbed 

 and swollen, and frequently dividing into two branches, 

 the whole adhering closely to the glass. After a day 

 or two's growth in this manner, a perpendicular stem 

 begins to shoot from some point of this creeping root, 

 and soon separates into four straight, slender, slightly 

 divergent tentacles, which shoot to a considerable 

 length. The whole is of a crimson hue, with the 

 exception of the growing extremities of the creeping 

 root, which are pellucid white. The little creature is 

 now a Polype of four tentacles. (See fig. 10). 



I could not follow the development farther, for 

 though I had perhaps, a dozen in this stage, on the 

 bottom of the glass, they all died without farther 

 growth. And though, for weeks after, many gemmules 

 were deposited, and I could see plenty every day 



