CLASS IL— ORDER J. 



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. 



