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GENUS I. LOPHOHELIA (M. Edw. & Haime). 



Madrepora (Linn.). 

 Oculina (Lamarck). 

 Lithodendron (Schweiggeb). 



Corallum tree-like, or forming a branching thicket, 

 the branches coalescing; the form results from a 

 gemmation irregularly alternate and sub-terminal. 

 There is no true ccenenchyma, but the walls are very 

 thick, scarcely ribbed. 



Calices having a deep cavity, with a reverted 

 lamellar edge. 



Columella and palules wanting. 



Plates entire, salient, unequal, the principal ones 

 .united towards the lower part of their inner edges, 

 at the bottom of the visceral cavity. 



There is but one known British species, L. prolifera. 



