CORAL. 109 
is full of little cavities, permeated by a milky fluid; these are the 
chambers of the members of the association. This cortex is full 
of little hard bodies, called spicule, of which we have sketched 
AN ENLARGED SECTION OF A STEM OF CORAL, 
some specimens. Beneath the crust is the coral, properly so called : 
it is as hard as marble; its surface is remarkable for its stripes ; 
its colour is a beautiful red; and it is so hard that it is capable 
of receiving a very fine polish. The ancients believed that coral 
