250 NATUEAL HISTOEY OF 



Hab. : Widely distributed on rocks and algae between 

 tide marks. 



The young cells are whitisb^ becoming grey and 

 coarse when old. The cells vary considerably in ap- 

 pearancOj being sometimes elongated and decorated 

 with marginal tubercles and cross ribs^ at other times 

 without ribs or tubercles ; sometimes with a number of 

 ridges proceeding from a central raised area, at other 

 times almost plain ; sometimes with prominent spines, 

 at others with inconspicuous ones. The cells are always 

 more or less dotted with perforations, and there is 

 usually an avicularium on each side of the orifice. 



3. C. ANNULATA, Fobricius. 



Cellepora annulata [Fabr.), Lepralia annulata [Busk, 

 G.J., J). L.), Escharipora annulata (Smitt). 



Hab. : Shetland {A. M. N.), Cumbraes (D. L.), 

 Oban (T. H.), St. Andrews (McL), Cornwall {T. 



This species is called by its earliest discoverer, 

 " pulcherrima et perfectissima haec omnium visarum." 

 Dr. Landsborough calls it a very pretty species, and 

 describes each cell as being like a little barrel closely 

 hooped, and having transverse rows of perforations 

 betwixt the hoops. There is often a median line from 

 the top to the bottom of the cell. The colour in 

 general is a pale brownish-red. 



There are often three or four spines in the upper 

 margin of the cell. 



4. C. FiGULARis, Johnston. 



Lepralia figularis {G. J., D. L., T.H., G^-ay, Busk), 

 Escharipora figularis {Smitt). 



Hab.: Cornwall (C. W. P.), Guernsey {T. E.), 

 Hastings (Miss Jelly). 



