BRITISH ZOOPHYTES. 275 



Cellepora pertusa (Esper), C. perlacea {Thompson), 

 Escharina pertusa (M.-Edw.), E. perlacea (M.-Edw.), 

 Escharella pertusa (Smitt). 



Hab. : Isle of Man (Forbes), Cornwall {C. W. P.), 

 South Devon, Guernsey {T. H.), Sana Island [Hynd- 

 man), Shetland {A. M. N.) . 



This species occurs in orange-coloured colonies in- 

 crusting rocks and shells. The zocecia are ovate, 

 punctui-ed, distinct, each with a somewhat circular 

 orifice, the margin of which is thickened and without 

 spines. Sometimes there is an umbo or tubercle below 

 the orifice. The orifice is narrowed just above the 

 lower margin by two projecting denticles. 



6. L. Hippopus, Smitt. 



Hab. : Coast of Northumberland {Alder) . 

 The locality named is that of the only British 

 specimen of this species which has been noticed. 



7. L. EDAX, Busk. 

 Cellepora edax {Busk, Hinchs). 

 Hab. : Plymouth, Guernsey (T. K). 



This species is found incrusting the shells of uni- 

 valve molluscs, into which it has the power of eating, 

 so as to ultimately remove the entire shell, " its own 

 zoarium supplying a good and solid substitute for the 

 house which it has supplanted." — Hincks. 



The colonies are red in colour, and the separate 

 zooecia are irregularly shaped and arranged. The 

 margins are punctured, and below the orifice is a boss 

 or umbo. The surface of the cell is striated. The 

 orifice is rounded, contracted in the middle, with a 

 slightly curved lower margin. 



The avicuforia are placed on distinct areas between 

 the cells. 



T 2 



