82 



POPULAR ILLUSTRATIONS OF 



at least in which the hydrothecse may be more easily distinguished 

 by the naked eye. In one of these, T. muricata, the cells are 

 covered with spinous ridges. The other is a rare species, called after 

 Mr. Bean, of Scarborough, its discoverer. 



Figure 104 (p. 81) is an example of the larger genus, Sertularia. 

 It was called the "Great Tooth Coralline" by Ellis, and looks, in its 



Fig. 107.Antenmilaria antennina (magnified); common on shells and rocks in deep water; 

 polyps yellowish white. 



Fig. K)8.Plumulariapinnata (magnified); on shells and stones in deep water; polyps 

 reddish. 



Fig. IW.Campanularia verticillata (magnified); on shells: " Horsetail Coralline." 



natural condition, when attached to a fucus or shell, like long threads 

 of small " glistering pearls." One of the species, S. argentea, when 

 mature is a very striking object. The stem is regularly divided, 

 like that of a plant, by nodes, from each of which springs a whorl 

 of branches in which the polyp cells are fixed. It attains the length 



