353 
HELMINTHOLOGY. 
ceous tentacula or feelers, as fhovvn in the annexed 
-copi er-plate at fig. 12 ; but more particularly defcribed 
under the article Hydra, where the fpecies are cor¬ 
rectly delineated in an appropriate Engraving. • They 
principally inhabit ftagnant pools, and gently-flowing 
Dreams, in England, and moft parts of Europe. 
•The Helminthology Plate V. is given to .illuftrate more 
fatisfaftorily tliis order of' zoophytes. Fig. 1. repre- 
fents the tubipora ferpens, compofed of fhort rows of cir¬ 
cular parallel tubes, of a white or rofeate colour, creep¬ 
ing or multiplying upwards ; which, in this fpecies, ap¬ 
pears to be its mode of generation, till they become de¬ 
ciduous, and fall off at the top, in order to plant or pro¬ 
pagate new colonies. This curious fpecies is very mi¬ 
nute, being often attached to the tlalks of fiici, and with 
them waflied on fhore. In the engraving it is much 
magnified. 
Fig. 2, is the madrepora crijlata, of the natural fize, 
Blowing its foliaccotts conftrudtion, with rows of ftars 
impreffed in the centre, which are its mouths, and all 
equally furnifhed with tentacula. The lamellae or gills 
are of a fiony hardnefs, which conftitute the coral, 
formed of the gelatinous matter continually thrown out 
by the animal, and of which the whole mafs is formed. 
This is commonly found of a pale blue grey, or-finning 
light ftraw-colour, or white freaked with pale red. 
Fig. 3, the millepora truncata, a beautiful white coral, 
growing eredl, with dichotomous.truncate branches, at 
the ends of which the pores or mouths of the animal 
are placed. , This is often variegated with a tint of yel¬ 
low or grey, highly polifhed, and appearing as if var- 
niflied. 
Fig. 4, is a fpecies of rdd coral, th e ifis coccinea, of a 
beautiful branched form, covered with fmall fcarlet 
prominent cells, occupied by oviparous polypes. 
Fig. 5, a fmall branch of the antipatkes ulex, a fpecies 
of black coral, found in the Indian Ocean, of various 
magnitudes, furniflied with numerous ovate yellowifh- 
brown vehicles, lodged upon the branches, and fuppofed 
So be the ovaries. 
Fig. 6, the alcyonium lyncuriwn , from the Cape of 
Good Hope. It is a beautiful fpecies ; globular, car¬ 
tilaginous, and tuberculate, befet with polype-bearing 
ftellate cells. They adhere very firmly to pieces of 
rock ; and are about the colour and fize of an unripe 
orange. « 
Fig. 7, is a very delicate fpecies of fponge, (fpongia 
ofgformis,) found adhering to the bafes of the Norwe¬ 
gian rocks. This is of a light orange or lemon colour, 
Hightly branched, and thickened round the pores. 
Fig. 8, the tubularia magnified ; a fpecies lately difeo- 
vered in the Welt Indies-, and by far the largefl and moil 
fplendid of the genus. Like the reft of its tribe it has 
the faculty of drawing its tentacula within the tube, and 
the tube within the rock on which it refides. It fieems 
to conned: in fome meafure the genera Tubularia and 
Amphitrite, having the annulated wrinkled tube of the 
former, and the re.tradi.le radiated tentacula of the lat¬ 
ter. It is mod probably oviparous. At <z, is fhown ano¬ 
ther, much fmaller, fuppofed to be a young animal of 
the fame fpeciesv 
Fig. 9, the corallina officinalis ; already defcribed un¬ 
der that article, but no figure of it is there given. This 
is commonly ufed in medicine as an helminthic, but pro¬ 
bably without the fmalleft fuccefs; for it appears to 
have been firft recommended as a fpecific for worms 
only on account of its fuppofed likenefs to the maw or 
thread-worm. 
Fig. 10, fertularia geniculata j taken at firft by Mr. El¬ 
lis for a coralline; but it has all the characters of a 
true fertularia ; and is furnifhed with veficles or ovaries 
in a kind of cup-fhaped denticles placed on the branches, 
containing eggs, or the living young. The polypes 
have a numerous feries of exfertile tentacula, but fcarce- 
ly vifible to the naked eye. This figure is eonfiderably 
magnified. 
Fig. 11, pennatitla Jltllifera, a fmall fpecies 6f the fea- 
pen. It is furnifhed with folitary polypes towards the 
tip, placed on oppofite fides alternately; the Item thick¬ 
ened, and obtufe beneath. It inhabits the Northern 
Seas; and is generally of a flefh-colour. Some of the 
fpecies emit a very fplendid phofphoric light in dark 
nights, 
Fig. 12, hydra grifea, 4 true polype in its expanded or 
adtive ftate, feeking its prey. Thefe wonderful ani¬ 
mals, which are found in'our ponds and rivers, are of a 
(lender form, fiirniftie'd round the mouth with from eight 
to twelve filiform tentacula, which they can wholly 
contract, or let fall to a great length, When in queft 
of food, they cement themfelves by the bafe or tail' to 
any convenient fubftance, and then expand their tenta- 
cula for the purpofe of feizing their food, which, when 
taken hold of, they draw it up to the mouth, fituated 
at the bafe or rooj: of thefe thread-like arms or feelers. 
The mouth is poffeffed of an expanfive power, adapted 
to the fize of its prey; and which, when fwallowed, en¬ 
larges the natural fize of the trunk or body, exaftly 
fimilar to that of a ferpent after fwallowing an animal 
larger than itfelf. The common food of polypi are 
fmall water-worms; ’(gordius aquaticus,) and monoculi, 
vulgarly called the water-flea. Thefe they entangle in 
their feelers, which they contract by twifting them in a 
fpiral form, and thus by degrees draw them up to the 
mouth. This curious artifice is correCHy rCprefented 
in the Engraving ; where a fmall water-worm is feen 
carried up to the mouth of the polype ready to be de¬ 
voured ; another is feized by different tentacula and 
on the oppofite fide a monoculus alfo ; each of which 
the little voracious polype will greedily fwallow in turn; 
and, when fated, retradls its tentacula, and retires 1 to 
reft, in its quiefeent (fate, appearing like a bit of green 
jelly. Its young, are produced by a fort of buds iffuing 
from its fides, appearing at firft like minute papillte, 
till, increafingin fize, they affume the appearance of the 
parent polype; and then, dropping off, immediately 
fhift for themfelves. But its moft wonderful faculty, 
is, that of reproducing its parts when broken off; or, 
if cut in pieces, each piece grows into a diftinCt polype. 
—See this fubjeft more fully treated under the generi- 
cal title Hydra. 
The two genera in this order which are moftly fought 
after as affording the fine red and black coral, are Ifis, 
and Gorgonia ; and thefe conftitute a valuable fource of 
commerce. Next to them are the Tubipora, Madrepoj’a, 
Millepora, and Tellepora, which produce the white co¬ 
ral, denominated lithophyta> becaufe in thefe the coral or 
bdne of the animal is external or naked ; whereas in the 
other genera it is clothed with a flefhy epidermis ,or 
bark. 
The feafon for fifhing coral is from April to July; 
the places are the Perfian gulf, the Red fea, coafts of 
Africa, the ifles of Majorca and Corfica, and the coafts“ 
of Provence and Catalonia, Medina, Sc c. Spallanzani 
has particularly defcribed that which is carried on in 
the ftrait of Medina. This fifhery extends from the en¬ 
trance of the Faro to the part of the ftrait oppofite to 
the Church of the Grotto, being a tradt fix miles in 
length, and to the diftance of three miles from Meflina. 
The rocks which produce the coral are fituated almoft 
in the middle of the ftrait, at different depths, from 350 
to 650 feet. The, bottom and caverns of the rocks are 
the places from which they endeavour to bring tip the 
coral with their nets; and it is a conftant obfervation; 
that every branch is perpendicular to the plane on which 
it grows, without ever turning on one fide. Coralj it- 
is laid, grows more plentifully in places fituated to-"the 
eaft- than in thofe to the fouth ; it is rarely found to the 
vtfi&j and never to the north. In the firft fituation it is 
generally 
