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CORALLIUM. 
A tree-like, inarticulated Polypidom ; axe stony, 
stiff, and susceptible of a beautiful polish ; rind 
fleshy, becoming chalky and very friable by desicca- 
tion, and adhering to the axe. 
The Coral is a Polypidom resembling a small tree 
deprived of its leaves and twigs, having nothing left 
but the trunk and branches ; it is fixed to rocks by a 
large base, from which it rises to the height of three 
decimetres. 
It is composed of a calcareous axe, and of a gela- 
tino-cretaceous rind : the axe is equal to marble in 
hardness ; it is formed by concentric layers, which 
become perceptible by calcination ; its surface is 
more or less striated, the striae are parallel, and un- 
equal in depth. 
A reticulated body, formed of small membranes, 
with numberless vessels and glands filled with a milky 
juice, appears to unite the rind with the axe ; this re- 
ticulated body is found in all corticiferous Polypi- 
doms : the rind is of a less deep colour, of a soft sub- 
stance, and formed of small membranes and slender 
filaments ; it is pierced by tubes or vessels, and co- 
vered with tubercles which are thinly scattered and 
have a large base, the summit of which is terminated 
by an opening divided into eight parts. In the interior 
is found a cavity which contains a white and almost 
transparent polypus. Its mouth is surrounded by 
