022 HYDRA, 
the polype with the microftope, thefe particles were per-' 
ceived to be driven about the ltomach, and to pafs from 
head to tail, and into their arms, even where thefe were 
as fine as a thread ; they were afterwards forced into the 
ltomach,' and from thence to the tail, from whence they 
were again driven into the arms, and fo on. 
The polypes feed on the greater part of thofe infedts 
that are to be found in frelh water. They may be nou- 
riihed with worms, the larva of gnats, &c. they will alio 
eat larger animals if they are cut into fmall pieces, as 
Inails, large aquatic infedts, fmall fifh, butcher’s meat, See. 
Sometimes two polypes feize the fame worm, and each 
begins to fwallow its own end, continuing fo to do till 
their mouths meet. In this pofition they remain for fome 
time; at laft the worm breaks, and each has its lhare j 
fometimes the combat does not end here, for, each conti¬ 
nuing to difpute the prize, one of the polypes opens its 
mouth advantageoufiy, and fwallows the other with its 
portion of the worm. 'This combat ends more fortu¬ 
nately for the devoured polype than might be at firft ex¬ 
pected, for the other often gets the prey out of its fto- 
mach, but lets the polype itfelf out again found and fafe, 
after having imprifoned it above an hour. From hence 
we learn, that the ltomach of the polype, which fo foon 
dilfolves the animal fubftances which are conveyed into 
it,, is not capable of digelting that of another polype. 
If one of thefe creatures be examined in fummer, when 
they are molt adtive, and more particularly prepared for 
propagation, it will be found to Ihoot forth from its fide 
leveral little tubercles, or knobs, which grow larger and 
larger every day; after two or three days infpedtion, what 
at firft appeared but a fmall excrefcence, takes the figure 
of. a fmall animal, entirely refem’oling its parent. It does 
not inclofe a young polype, but is the real animal in mi- 
niature, united to the parent, as a lucker to the tree. 
When a young polype firft begins to Ihoot, the excref¬ 
cence terminates in a point, fo that it is rather of a coni¬ 
cal figure, and of a deeper colour than that of the body. 
This cone foon becomes truncated, and in a little time 
appears cylindrical. The arms then begin to flioot from 
the anterior end. The tail adheres to the body of the 
parent, but grows gradually fmaller, till at laft it only 
adheres by a point. It is then'ready to be feparated 5 for 
this purpofe the mother and young ones fixthemfelves to 
the lubltance upon which they may be fituated. They 
have then only to give a Hidden jerk, and they are di¬ 
vided, and become two diftinft beings. There are fome 
trifling differences to be obferved now and then in their 
performing this operation, which it would be too tedious 
to enumerate. The young ones Ihoot in proportion to 
the warmth of the weather, and the nature of the food 
eaten by the mother; fome have been obferved to be per¬ 
fectly formed in twenty-four hours, while others have 
required fifteen days for the fame purpofe ; the firft were 
produced in the midft of fummer, the latter in. a cold 
feafon. 
The tail of the young polype communicates with, and 
partakes of, the food from the parent, in the fame man¬ 
ner as its own arms do, and the food lies in the fame 
manner as in the arms. When this foetus is furniftied 
with arms, it catches its prey, fwallows,. digefts, and At¬ 
tributes the juices thereof even to the parent body; every 
good is common to each. Here then we have evident 
communication between the foetus and the mother ; this 
communication was further proved by the following ex¬ 
periment : A large polype, one of the hydra fufea, was 
placed on a flip of paper, in a little water ; the middle of 
the body of the young one was cut, and the fuperior part 
of that end which remained fixed to the parent was found 
to be open. The parent polype was then cut on each 
fide of the Ihoot. Thus a’ihort cylinder was obtained, 
which was open at both ends. - This being viewed through 
a microfcope, the light was feen to come through the fide 
flip, or young one, into the ftomach of the old one. 
For further conviction, the cylindrical portion was cut 
lengthways.; on obferving thefe parts, not only the hole 
of the communication was diftindtly feen, but one might 
fee through the end of the young one. This communi¬ 
cation between the parent polype and its young ones may 
further be feen on feeding them ; for, after the parent 
has eaten, the bodies of the young ones fwell, being filled 
w f ith the aliments as if they themfelves had been eating. 
A- polype puts forth frequently five or fix young ones 
at the lame time. Trembley has had fome that have pro¬ 
duced nine or ten at the fame time, and when one drop¬ 
ped off another came in its place. Though this gentle¬ 
man had for two years thoufands of them under his eye, 
and confidered them with the moft fcrupulous attention 
he never obferved any thing like copulation. To be 
more certain on this head, he took two young ones the 
inftant they came from their parent, and placed them in 
feparate glaffes ; they both multiplied, not only them- 
feives, but their offspring, which were feparated and 
watched in the fame manner to the feventh generation ; 
nay, they have even the faculty of multiplying while they 
adhere to the parent. The arms of the young ones do 
not fprout till the body has attained fome length. Seve¬ 
ral excrefcences or buds often appear at the fame time 011 
a polype, which are fo many polypes growing from one 
trunk ; whilft thefe are developing, they alfo bud, which 
buds again put forth little ones, the parent and the young 
ones forming a Angular kind of animal fociety, in which 
all participate of the fame life, and the fame wants. In 
this ftate, the parent appears like a Ihrub thick fet with 
branches. Several generations are often thus attached to 
one another, and all to the parent polype ; after a time, 
this tree of polypes, or hydras, is decompofed, and gives 
birth to new generations, or frefli genealogical trees. 
Here we fee a furprifing chain of exiltence continued, and 
numbers of animals naturally produced, without any union 
of fexes ; every polype railing a numerous pofterity by a 
kind of animal vegetation. 
So ftrange is the nature of this creature’s life, that the 
method'by which other animals are killed and deftroyed 
becomes a means of propagating thefe. When divided 
and cut to pieces in every direction that fancy can fug- 
gelt, it not only continues to exilt, but each 1’eCtion be¬ 
comes an animal of the fame kind. A polype cut tranf. 
verfely or longitudinally, in two or three parts, is not 
deftroyed ; each part in a little time becomes a perfedl 
polype. This fpecies of fecundity is fo great in thefe 
animals, that even a fmall portion of their fkin will be¬ 
come a little polype, a new animal riling as it.were from 
the ruins of the old, each fmall fragment yielding a po¬ 
lype. If the young ones be mutilated while they, grow 
upon the parent,the mutilated parts are re-produced ; the 
fame changes l’ucceed alfo in the parent. A truncated 
portion will put forth young before it is perfedtly formed 
itfelf, or has acquired its new head and tail; fometimes the 
head of the young one fupplies the place of that which 
would grow out of the anterior part of the trunk. If 
a polype be flit, beginning at the head, and proceeding 
to the middle of the body, a polype will be formed with 
two heads, and will eat at the fame time with both. If 
the polype be flit into fix or feven parts, it becomes a 
hydra with fix or feven heads. If thefe be again divided,, 
we fliall have one with fourteen ; cut off thefe, and as 
many new ones will fpring up in their place, and the 
heads thus cut off will become new polypes, of which fo 
many new hydras may again be formed ; fo that in every 
refpedt it exceeds the fabulous relation of the Lernean. 
hydra. 
As if the wonders already related of the polype were 
not fufficient to engage our attention to thefe Angular 
animals, new circumftances, as furprifing as the foregoing, 
prefent themfelves to convince us of the iinperfedtion of 
our ideas of animality. The polypes may be as it were 
grafted together. If the truncated portions of a polype 
be placed end to end, and then puflied together with a 
gentle force, they will unite, and form a Angle one. The 
, union 
