144 
GENERA OF CLASS III. 
whitish, soft, and corky ; this axe is enveloped either 
in a gelatinous and fugitive exterior, or a fleshy rind of 
greater consistency, which is animated and frequently 
irritable, becoming more or less cretaceous by desic- 
cation, and enclosing the Polypi, as well as their cells, 
when there are any. 
Anadyomena. Fan-shaped, furrowed with articu- 
lated and symmetrical nerves ; almost transparent, 
and enveloped with a gelatinous substance. 
Antipathes. Tree-formed, simple or branched ; 
axe horny, usually hairy or stuck with small spines, 
rarely smooth ; rind polypiferous, gelatinous and slip- 
pery, almost wholly disappearing by desiccation* 
Gorgonia. Polypidom tree-formed, simple or 
branched; branches dispersed or coming from the 
sides ; free or anastomosed ; axe longitudinally stri- 
ated, hard, horny, and elastic, or pithy and brittle ; 
rind fleshy and animated, becoming cretaceous by 
desiccation ; polypi either not projecting beyond the 
rind, or when dead forming small tubercles on its 
surface. 
Plexaura. Tree-formed, branching, and frequently 
dichotomous ; branches cylindrical and stiff ; axe 
slightly compressed ; rind, in a state of desiccation, 
corky or earthy, very thick, and effervescing in acids ; 
covered with large and numerous dispersed cells, 
frequently of unequal sizes, and never projecting. 
Eunicea. Tree-formed and branching ; generally 
compressed, and mostly so at the junction of the 
