GENERA OF CLASS III. 
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branches ; covered with a thick cylindrical rind, irre- 
gularly set with polypeau projections. 
Primnoa. Tree-formed and dichotomous, with long 
and conical projections, internally as well as exter- 
nally formed like bags or purses, which are pendent, 
imbricated, and covered with scales that are also im- 
bricated. 
Corallium. Polypidom tree-formed and inarticu- 
lated; axe stony, stiff, and susceptible of a high 
polish ; rind fleshy, becoming cretaceous and very 
friable by desiccation, and adhering to the axe. 
GENERA 
BELONGING TO THE THIRD ORDER OF THE THIRD CLASS. 
Tree-formed Polypidoms ; composed of a rind, 
similar to that of the last order, but with an articu- 
lated axe; the articulations alternately horny or 
corky, and calcareously stony. 
Melitea. Polypidom tree-formed and knotty ; with 
branches generally anastomosised ; stony articulations, 
substriated; the intermediates spongy and swelled; 
rind cretaceous, very thin, and friable in a state of 
desiccation ; polypi on the surface, or tubercular. 
Cor. 
T 
