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GENUS I. CARYOPHYLLIA (Lamarck). 



Cyathina (Ehbbnb.). 



Corallum simple, generally obconic, often with an 

 expanded base, permanently adherent ; outline ovate 

 or circular. 



Columella composed of several thin, narrow, twisted, 

 vertical plates. 



Palules broad, entire, in a single circle. 



Plates straight, broad, projecting, and forming six 

 systems. 



Bibs straight, developed only towards the summit, 

 granulated. 



The animal (for so we may conventionally term the 

 soft tissues, though it is to be remembered that the 

 corallum is an essential part of the living body) is, so 

 far as we know it, translucent, the column very exten- 

 sile, the disk protrusile, the tentacles set in several 

 rows, diminishing in size from the outer row inward, 

 each consisting of a stem with a globular head. 



I know but one British species, C. Smithii. 



