POL 
added, as it is a method of propagation fo com- 
mon to all the tribes of infeft nature; but with 
regard to fuch as are produced like buds from 
their parent ftem, or like cuttings from an origi- 
nal root, their hiftory requires a more particular 
explanation. 
If a Polypus be carefully obferved in fummer, 
(when thefe animals are chiefly aftive, and more 
particularly prepared for propagation) it will be 
found to protrude from divers parts of it's body 
feveral tubercles or fmall knobs, which gradually 
become larger and larger : after two or three days 
infpeftion, what at firft appeared but a fmall ex- 
crefcence, afifumes the figure of a minute animal, 
entirely refembling it's parent, furniflied with feel- 
ers, a mouth, and all the requifite apparatus for 
feizing and digefting it's prey. This little crea- 
ture continues to increafe, like the parent to which 
it is attached ; fpreads it's arms, in order to lay 
hold of whatever infed: is proper for aliment, and 
then devours it for it's own particular benefit: 
thus it is poffeflTed of two fources of nourifhment; 
that which it receives from the parent by the tail; 
and that v/hich it's own induftry acquires by the 
mouth. The food which thefe infedts receive of- 
ten tin6lures their whole bodies ; and on this oc- 
cafion the parent is often feen communicating a 
part of it's own fluids to that of it's attached pro- 
geny ; while, on the contrary, it never acquires any 
tin6ture from the food or juices of it's young. If 
the parent fwallows a red worm, which gives a 
colouring to all it's fluids, the young one partici- 
pates of the parental tinfture; but if the latter 
fhould feize on the fame prey, the parent Polypus 
is no way advantaged by the capture, but ail the 
benefit remains with the young one. 
We are not, however, to imagine, that the pa- 
rent is capable of producing only one young Po- 
lypus at a time; feveral are thus feen at once, of 
different magnitudes, growing from it's body; 
fome juft budding forth; others acquiring their 
perfect form ; and fome arrived at fufficient matu- 
rity, and juft ready to drop from the parental ftem. 
But, v/hat is ftill more fingular, thoie young ones 
themfelves, that continue attached to their parent, 
are obferved to propagate their young alfo, each 
holding the firne dependance on it's refpeftive 
parent, and poffclTed of the fame advantages al- 
ready defcribed in the firit connexion. Thus we 
behold a furprifing chain of exiftence continued; 
and numbers of animals naturally produced, with- 
out any union of the fexcs, or other previous dif- 
pofition of nature. 
Indeed, this Icems to be the moft natural way 
by v/hich thefe animals are multiplied; their pro- 
dufcion from the egg being Icfs common : and 
though fome of this kind are found with little 
bladders attached to their bodies, fuppofed to be 
replete with eggs, which afterv/ards come to ma- 
turity; yet the artificial method of propagating 
thefe animals is much more expeditious, and 
equally certain. Itfeems of no confequence whe- 
ther one of them be cut into ten, or ten hundred 
parts ; each becomes as perfeft an animal as that 
which was originally divided. But it fhould be 
obferved, that the fmaller the part is which is thus 
feparated from the reft, the longer it will be in 
,coming to maturity, and alTuming it's perfe(5l 
form. 
It would be endlefs, and perhaps uninterefting, 
to recount the numerous experiments which have 
been tried on this minute prodigy : the animal has 
POM 
been twlftcd into all mahner of fnapes, turned iri- 
fide out, and cut in every diredion; yet ftill it 
continued to move; it's parts adapted themfelves 
again to each other; and, in a fiiort time, it be- 
came as voracious and induftrious as before. 
Befides the Polypi obferved and defcribed by 
Mr. Trembley, there are various others which 
have been lately difcovered through the vigilance 
of fucceeding obfcrvers; and fome of thefe fo 
ftrongly refemble a flowering vegetable, that many 
naturalifts have miftaken them for fuch. Hughes^ 
in his Natural Hiftory of Barbadoes, has defcribed 
a fpecies of this animal under the appellation of a 
fenfitive flowering plant. He obferved that it 
took refuge in the holes of rocks; and, when un- 
difturbed, fpread forth a number of ramifications, 
each terminated by a flowery petal, which fhrunk 
from the approach of the hand, and withdrew into 
the hole from whence it had been perceived to 
iffue. This plant, however, was no other than 
an animal of the Polypus kind, which is not only 
found in Barbadoes, but alfo on fome parts of the 
Britifh coafts, and along the fhores of the conti- 
nent. 
The reprodu6lio"n of it's parts, though one of 
the moft extraordinary properties of the Polypus, 
feems by no means peculiar to it alone. If a lob- 
fter or crab lofe a limb, it's place is always fup- 
plied with a frefh one: and Bonet, Lyonet, Reau- 
mur, and Folkes, have all found, on experiment,; 
that feveral earth and aquatic worms have the 
fame property, fome of them even when cut into 
numerous portions. The urtica marina, or fea- 
nettle, has been obferved to have the faculty of 
reproduftion; and particularly the fea-ftar, a real 
fpecies of the Polypus, has long been known to 
poflTefs the fame virtue. 
Polypus is alfo an appellation given by fome 
of the earlier writers to the thin-fhelled nautilus, 
or nautilus papyraceus. The body and arms of 
this creature fom-ewhat refemble thofe of the Po- 
lype; and it was fuppofed to be a fpecies of Polype 
cnclofed in a fhell, which it could occafionally 
quit, in order to feed afliore, 
POLYSACTTNODOS. A name by which 
fome naturalifts exprefs thofe ftar-fifti whofe bo- 
dies are divided into more than five rays. 
POLYTHALAMIUS. A term ufed by 
Breynius, and fome others, to exprefs a clafs of 
fliells: the charaders of which are; that they are 
hollow, either ftraight or fpirally twifted; always 
wide at the mouth, and growing narrower to the 
other extremity. They are divided into feveral 
cells or chambers, called thalami, each feparated 
from the other by a diaphragm, or partition of 
fhelly matter: the upper or largeft chamber con- 
tains the body of the animal; but all the others 
are perforated by a fiphunculus, giving them a 
communication with each other, and running 
from the mouth to the very apex. 
Breynius makes four genera of this clafs ; the 
ortlioceros, lituus, ammonites, and nautilus. 
POMATIA. A large fpecies of garden-fnail, 
fo called from it's feeding on apples and other 
fimilar fruits. It is originally a native of Italyi 
but has been introduced into Britain, where it is 
now very common. 
This animal is reckoned a fovereign remedy in 
confumptive decays ; and has therefoi'e been pro- 
pagated in this country, in fome places with affi- 
duity and abundant fuccefs. 
The Pomatia is much larger than the common 
fnail. 
