504 CLASS ECHINODERMATA. 
FLusTRA, L., 
Present a great number of cellules, united like the combs of 
bees, and sometimes covering divers bodies, sometimes form- 
ing leaves or stems, of which one side only is furnished with 
cellules in certain species, and both in others. Their sub- 
stance is more or less corneous. (Flustra foliacea, Gm. 
&c. &c.) 
CELLEPORA, Fadri., 
Present accumulations of little cellules, or calcareous vesicles, 
crowded one against the other, and each pierced with a small 
hole. (Cellepora hyalina, Gm., &c.) 
TUBULIPORA, Lam., 
Are accumulations of little tubes, the entrance of which is as 
broad as or broader than the bottom. (Millepora tubulosa, 
Gm ) 
Some bodies exist in the sea, pretty similar to polyparia, 
in their substance and general form, but in which no polypi 
have as yet been observed. Their nature is therefore doubt- 
ful; and some great naturalists, such as Pallas, and others, 
have considered them to be plants. Nevertheless, there are 
several who regard them as polyparia, with polypi, and with 
cells exceedingly small. If this conjecture be true, they must 
belong to the present order. Those among them whose inte- 
rior is filled with corneous filaments present, however, some 
analogy with the CERATOPHYTES. 
CoRALLINA, L., 
Have articulated stems, supported on a sort of roots, divided 
into branches equally articulated, at the surface of which no 
pores are visible, and in which it has not been possible to per- 
ceive any polypi. 
