5 II fl
18. Sertularia fpinofa. Silk Coralline.
Sertularia mollis ramofa
pellucida, ramulis . cre-
berrimis teneris dichotomis,
Jpinis terminantibus, den-
ticulis obfoletis fecundis dif-
tantibusy ovariis. veftculcs-
farmibus.
This Coralline is fmooth,,
tranfparent, and branched ;
the fmaller branches are. very
tender, many, dichotomous,
and gradually end in- points •
the denticles are hut juft visible,
and placed at a diftanee
from each other on the famé
fide, from whence the ovaries
that are like veficles proceed.
Silk Coralline. Ellis Corallin. pag. 20. tab. 11. No. n
fig. b. d. B. C. D.
Sertularia fpinofa. Linn. Syft. Nat. Ed. 12. p. 1312.
This Coralline has fomething very fingular in it, each
polype-head being inclofed in a veficle, which falls off
when the head decays : whether thefe are the ovaries as
well as mouths to fupply the animal with food, future
obfervations muft explain to us, but at prefent it feems:
moft probable.
19. Sertularia dichotoma. Sea-thread Coralline.
Sertularia longijftma ra-
mofa dichotoma, denticu-
lis campanulatis, pedun-
Culis annulofs, ovariis
ovatis axilharibusy pedun-
culis contortis..
This Coralline is very long„
and branched in a fubdivided
manner§ it has bell-fhaped
denticles, fupported by ftalks
full of rings: the ovaries are
oval, and fit upon twilled foot-
ftalks at the infertion of the.
branches.
S.ea-
Sea-thread Coralline. Ellis Corallin. pag. 21. tab. 12.
No. 18. fig.-a. c. A. C.
Sertularia dichotoma. Linn. Syft. Nat. Ed. 12. p. 1312.
It is found on the Suffex coaft, but in greater plenty
on the coaft of Holland.
Knotted Sea-thread Coralline.
This Coralline has alternate
cup-lhaped denticles, with
twilled ftalks; the ovaries are
oval, and flattilh at top.
20. Sertularia geniculata.
Sertularia denticulis al-
ternis calyciformibus, pe-
dunculis contortis, ovariis
ovato-truncatis axillari-
bus.
Knotted Sea-thread Coralline. Ellis Phil. Tranf. Vol.
48. tab. 22. fig. .1. Corallin. pag. 22. tab. 12. No. 19.
fig . b. B.
Sertularia geniculata. Linn. Syft. Nat. Ed. 12. p. 1 31 2-
This creeping little Coralline has but few branches,
and they are alternate : it is found adhering by little tubes
to the podded Fucus, and fometimes to the Sea-Oak
Fucus. I have met with it on the coaft of Suffex, grow-
ing upon the Afcidia inteftinalis of Linn. Syft. Nat.
Ed. 12. p. 1087. which is a foft, white, membranaceous
animal, nearly egg-fhaped, that fixes itfelf by its bafe to
rocks and Ihells ; has two openings, one at the top and
the other a little lower, from whence it fquirts out the
water. On this the Knotted Sea-thread Sertularia, or
Coralline, fends forth its root-like tubes, nearly in ftrait
lines; from whence arife, at a fmall diftanee from each
other, young fprigs about an inch high, properly fur-
niftied with their denticles and polype-heads, fo as to
H form