ON POLYPI. 583 
the cellule, to which, doubtless, itis adherent by its extremity, 
which appears to be continued with the vessels of the fleshy 
and common envelope. ‘This at least is the opinion of M. de 
Blainville, who founds it on a supposed analogy with the 
pennatulz, which he has dissected. Donati, however, tells us 
expressly that it is entirely detached and separate. Be this 
as it may, the body of the polypus is terminated by eight ap- 
pendages, disposed in radii round the mouth, or an aperture 
which Donati informs us is made by a shell, a little widened 
at its root, with a large aperture at the summit, and hollowed 
by eight broad furrows, between each of which arises a sort 
of ridge. Between two of these elevations, is placed one of 
the tentacular appendages, which are thus upon the same 
plane. They are all perfectly equal, conical, a little com- 
pressed, and provided on each side with appendages, or 
barbles, regularly decreasing from the base to the extremity. 
Donati adds, that he has seen at the inferior part of the body 
of some polypi, some little hydatiform bodies, rather round, 
extremely small, soft, transparent and yellowish. He thinks, 
with reason, that these are the eggs, or reproductive cor- 
puscula. 
The coral lives in the Mediterranean sea only at consider- 
able depths, though rather variable. The coral seems to re- 
quire at least ten years to render its growth complete. Pro- 
pagation takes place thus: the eggs, or reproductive corpus- 
cula, rejected through the mouth of the animal, or rather, 
perhaps, through the orifices which are at its margin, fall 
upon some body, and adhere there by their soft and gelatinous 
nature. They extend a little, and begin to grow, particularly 
at the part in contact, which enlarges, and moulds itself on 
the submarine body. From the middle of this sort of coral- 
drop, rises a tubercle, in which are evidently seen an interior 
cavity, and eight wrinkles, or plates at its superior part, but 
without aperture. The polypus, in its interior, is as yet but 
