102 
room xi. shaped cells, but they are placed in lines across 
the two upper sides of a triangular tree-like 
coral. 
The cells of the Cellepora are distinct ven- 
tricose urn-shaped, with a round mouth, and 
united together into a spongy coral. The ge¬ 
nera Berenice and Discopora consist of similar 
cells, sunk into an expanded chalky crust. 
In the second division the mouths of the 
ceils are two-lipped, and the cells are united 
laterally on one or two planes into a crustaceous, 
or arborescent coral. In the genus Flustra 
the cells are very flat, and placed in a regular 
manner, forming a crust on marine bodies, or 
on one or both sides of an expanded foliaceous 
coral. The genus Electra differs from Flustra 
in the cell being ciliated, and placed round a 
cylindrical stem, and the Lunulites in the cell 
being thicker, and forming a cup-shaped disc, 
which is attached to sand or stone in its young, 
and free in its adult state. 
In the Cellarice the cells are placed in a quin- 
cuncial band round the joints of a cylindrical, 
forked coral, which is attached by fibrous 
tubular roots. 
In the family of Crissice the cells are placed 
in longitudinal rows, opening on one side of a 
forked, flat, subarticulated, branchy coral, at¬ 
tached by tubular fibres. In the genera Crissia , 
Chanda , Acharnarchis , and Bicellaria the cells 
are 
