which circulation is not fo eafily demonftrated in veger
tables.
From thefe connedted radical and flefhy tubes belonging
to the bafe of the Gorgonia, many young Items of the
fame fpecies frequently rife, which are furrounded with
little mouths; fo that when we confider them to be a
kind of Polype, we fhall not be furprized at this manner
of increafe, no more than we are at prefent at the cluf-
tered Animal Flower, or Adtinia fociata, defcribed in
the Philofophical Tran factions, Vol. 57. tab. 19. where
the young ones are produced from the adhering flefhy
tube, that proceeds from the bafe of the old ones.
Befides, i f we confider them to have the fame properties
with the Hydra, or frefh-water Polypes, which repeated
experiments prove to us are fo foon reproduced,
after they are either cut in pieces or maimed, we fhall not
be fo much amazed, when we meet with inftances of
the flefh of the trunk and ftem of the Gorgonia, which by
fome accident has mortified, and the furface of its bone
become rotten, and now the receptacle of many kinds of
extraneous marine animalcula, and yet find the branches
at top with all their mouths alive and in vigour. This
bony part fo decayed now grows no more than the fhell
o f the oyfter, when the fifh is dead. It becomes only a
bafis during the time it has ftrength left to fupport the
living part above, as the fhell or rock that fupports them
both below. But it often happens that the living part
above grows downwards, by pufhing forth connected radical
tubes and polype mouths on the dead part, as it
would on a rock, or any other firm bafis, to fecure itfelf
the better, forming at the fame time a new layer of bone,
or hard part, on the decayed flefh ; and this is the reafon
why in making crofs fedtions of fome of the ftems of the
larger
larger Gorgonias, we frequently meet with layers of
calcareous matter inclofed between the circles, which is
evidently nothing elfe but the decayed flefh o f the animal,
which has been covered and inclofed by the fubfe-
quent growth of the fame animal. This is totally different
from any thing that we know of in the growth of trees.
To explain the difference between the concentric circles
in a crofs fedfion of the horny part of a Gorgonia, and
thofe of wood, I have given in plate 2. fig. 6. 7. a figure
of a crofs and upright fedfion of a piece of wood (lignum
fantalum) magnified to fhew the utricular veffels, that
interweave the upright longitudinal veffels, proceeding
horizontally from the pith in the center through all the
circles to the bark on the outfide. In the fame plate, at
fig. 2. 3. is a horizontal fedtion of a Gorgonia cerato-
phyta, where the feveral waved laminas are feen adhering
together, but no appearance of crofs fibres.
Dr. Donati, who was remarkably careful in examining
the Red Coral, or Gorgonia pretiofa, tells us in the Philofophical
Tranfadtions, Vol. 47. pag. 97. “ That he has
“ obferved tranfverfe fedtions of fome pieces of this Coral,
which exhibit different lines, or annual bands,
“ whereof one part is of a rofe color, others yellowifh,
“ others white, and others more or lefs charged with co-
“ lor, which form concentric circles like the coats of an
“ onion.”
It is evident from hence, that there can be no circulation
of juices, or the colors would have been the fame.
It is not improbable that thofe different colors may be
owing to the difference of food at particular feafons ; for
we know that thofe animals with polype-like mouths on
their flefhy outfides have their appointed feafons of grow-
rng, which happen when they find more plenty of food
L at