lines is formed, as we find them on oyfters and other fhell-
filh, when we drag for them in deep water. Nothino-can
explain this extraordinary and wonderful proceeding
of nature fo clearly, of an animal produced by fuckers
like a plant, as the inftance I have already given in the
Philofophieal Tranfadtions, vol. 57. p. 436. of the in-
creafe of the cluftered Animal Flower, or Adtinia fociata,.
where the animal and its organs are large enough, without
the afliftance of a microfeope, to convince us of the
truth of this furprizing fadt; and yet thefe organs are totally
different from thofe of a plant. Here then we fee
branched animals formed as infedts are, with a horny
fheath to cover them, which anfwers the purpofe of bones,,
while the fofter parts are contained in the infide. When,
we view the different manner and various forms in which
thefe Sertularias grow, we fhall ftill find that, notwitfr-
ftanding their external appearance, they all agree in the
general charadter of this genus.
Some fend out but few and fhort tubes: from their bafe;
and rife up into firm ftiff fingle Items, growing thicker
and alfo broader at their bottom as they grow old -y fuch
as we may obferve in the Sertularia argentea, or Squirrel’s-
tail Coralline, S. Thuja, or Bottle-brufh Coralline, S.
abietina, or Sea-fir Coralline, and S.. Pinafter, or
Sea-pine Coralline, and many others. Some, arife from
little tubes ramified like a fponge ; thefe enter into,
and compofe large ftems, as in the. Sertularia an-
tennina, or Lobfter’s-horn Coralline, and the S. Myrio-
phyllon, or Pheafanc’s-tail Coralline. Some fend out
tubes more remote, from, whence arife fhorter and more
diftant branches, as the Sertularia pumila, or Sea-oak
Coralline, and the S. geniculata, or Knotted fea-thread
Coralline : but the mod lingular are thofe which, from a
congeries of little tubes, form ftems and branches, not
unlike
unlike the outward appearance of the Gorgonias, fuch as
the Sertularia verticillata, or Horfe-tail Coralline ; the
S. fpinofa, or Silk Coralline; the S. halecina, or Herring
bone Coralline ; and the S. frutefcens, or Shrubby
Coralline; thefe feem to form the firft or leading ftem as
a fupport for the next to climb up, fo that in feme old
ftems, particularly of the Herring-bone Coralline, I have
obferved the inner tubes of their ftems have been rotted
and deftroyed, by being inclofed by fo many others on
their furface. See page 18, Elfay on Corallines.
Some writers feem at a lofs to account for the growth
of thefe kind of Sertularias, whofe ftem and branches are
thus compofed of many capillary tubes, and therefore are
o f opinion, that their manner o f vegetating is obfcure,
and that probably they grow not only in length and
thicknefs', but likewifein fubftance and number of tubes,
as plants do.
In order to account for the tubes flicking together,
they fuppofe that they are provided with an intermediate
fubftance, by which feme are flightly glued
together, others rendered more compadl, and feme even
become folid and hard.
But it appears evidently on examination, that this gelatinous
fubftance is common to all the genus, and is no
other than what the radical parts of them all poflefs in
common, in order to adhere firmly to their feveral
ftations.
So that inftead of thefe radical tubes lying horizontally,
and adhering in lines like the Sertularia pumila, or Sea-oak
Coralline, on its fucus, and many others after the fame
manner, they raife themfelves up from their bafes (where
thefe little tubes are firft fixed) and fupport one another
by this natural gluten in an eredt form, making a ftem
F' 2 out