48 POPULAR HISTORY OF THE AQUAEIU:\r. 



with an occasional exception, for they are two, three, or four 

 abreast. Their substance is hyaline, but the contents are 

 opaque and flesh-coloured. Their shape is sub-oval, larger 

 at the tip ; but the sides are fluted, so as to form about six 

 rounded angles, and as many furrows. Near the tip, several 

 divergent tubercles or blunt spines are given ofl". The tuft 

 alluded to I put in a glass vessel made of the chimney of an 

 ordinary lamp, with the bottom closed by a plate of glass : 

 this was about half-full of sea-water. In three or four days, 

 examining cursorily with a lens, I was surprised to see the 

 bottom crowded with young polypes growing erect from 

 every part ; they were there by hundreds. I detached a few 

 for more particular examination. Each consisted of an ir- 

 regular, dilated, glossy plate, adhering to the bottom ; from 

 some point of which sprang up, erect, a slender tube, with 

 one or two joints, and terminating in a cell of the same form 

 as those above described. The medullary core permeated 

 the tube, and was developed into a perfectly-formed polype 

 inhabiting the cell and freely expanding from it. The tube, 

 the cell, and the polype, were of the same dimensions as in 

 the adult. Some of the cells already showed, in the form of 

 a tubercle budding from their bases, the commencement of 

 a new joint of the lengthening polypidom. 



