TUBULIPOUA LOBULATA. 445 



stragglings but the radiate form is the prevailing one. 

 The cells differ widely from those of /. serpens. They are 

 short and stout, and project very slightly from the crust. 

 For the most part they are horizontal, and generally not 

 connate, and they never form the deep, curved, transverse 

 rows which are so characteristic of the last species. The 

 dividing lines are generally absent, and the cells range in 

 longitudinal series, covering uniformly the front of the 

 branch. Sometimes, however, they are traceable on the 

 front of the branches, but disappear altogether in the 

 expanded terminations. In all cases the cells preserve 

 theii' distinctive character. The orifice is large and ellip- 

 tical. 



The branches are thick and usually broad, not much 

 subdivided, and of a dull purplish colour ; the texture is 

 much less delicate than that of /. serpens, and its bright, 

 vitreous surface is wanting. The zoarium has a decidedly 

 compact appearance, due to the shortness and horizontal 

 position of the cells. The branches flange outwards 

 towards the base, and are edged by an expansion of the 

 basal lamina. 



It may be added that the difi'erences between the two 

 forms are very apparent in the early stages of development. 



Habitat. On shells chiefly, from shallow to deep water. 



Localities. Dublin Bay (Hassall) : Isle of Man, off" 

 Maughold Head, extremely abundant ; Torbay ; Scotland, 

 on Pinna (T. H.) : Hastings (Miss Jelly) : Shetland, on 

 stone, 30-70 fathoms (A. M. N.) . 



Geographical Distribution. Scandinavian coasts 

 (Smitt) . 



