CLASS IL— ORDER I. 
GENERA AND SPECIES. 
Polypidoms plant-like, generally articulated, and 
formed of two substances : the one internal, or axe, 
which is membranous or fibrous, fistular or compact ; 
the other external, or rind, of various thickness, which 
is calcareous, and incloses the polypiferous cells, 
rarely visible to the naked eye: some genera ap- 
pear to have their polypi at the extremity of the 
branches or their divisions, or else they are found on 
the sides. 
TELESTO. 
Plant-like, branching, fistular, cretaceo-membra- 
nous, opaque, and longitudinally striated. 
These Polypidoms are generally found in thick 
tufts, attached to marine plants as well as rocks. 
