CELLULARIA. 341 
the base of some of the cells there arises a long setaceous 
bristle, that bends over the upper surface of the polypidom, 
and it is moveable. We doubt not that this formidable 
lash is to keep off intruders, and to sweep them away when 
they have made encroachments. 
*** Apertures superior and very large. 
6. CELLULARIA AVICULARIA, Bird’s-head Coralline, Hvis. 
(Plate XIX. fig. 72.) 
Hab. On corallines in deep water. Salcombe, common, 
Rev. T. Hincks; Peterhead, Mr. Peach. 
The polypidom is erect, bushy, greyish-white. The cells 
have a spine at each of the upper angles, and the aperture 
is generally covered with a round pearly operculum. ‘ On 
the outside of each cell we discover the appearance of a 
bird’s head, with a crooked beak, opening very wide.” 
(Hidis.) It is distinguished from Flustra avicularis by 
having two conical spines at the angles, whereas it (/. avi- 
cularis) has four, which also differ in appearance. The colour, 
likewise, is fainter when dried. I have it from Mr. Tuma- 
nowicz, Hastings. 
KEKE Anertures lateral and very large. 
7. CELLULARIA NERITINA, Wiss Blackburne. 
Hab. “ Miss Blackburne, Cheshire,” Dr. Fleming; Scar- 
