Encyclopaedia Britannica, or, a Dictionary of arts, sciences, and miscellaneous literature : enlarged and improved. Illustrated with nearly six hundred engravings > Volume 8, ELE-FOR

E R P E T
I'g.
Longeft finger, ij
Longelt toe, i
Even in the beginning of O&ober, the fifth toe of
the new foot was not vifible.
“ Experiment.— ,4 newt deprived of the right arm
and left hand. On the r 2th of June, I cut the left hand
and right arm off a newt: my chief objedf in this ex¬
periment was to verify Sig. Spallanzani’s affertion, that
nature reproduces exactly the portion amputated, which
was a faff of the utmoft importance in the theory of
animal reproductions, and could not be too well elta-
bliihed
“ Towards one fide of the feCtion, a little conical
nipple began to appear about the 7th or 8th of July, of
a violet gray colour. An incipient cleft, indiitmCtly
feen with the naked eye, was perceptible near themid-
dk of July : the papilla feemed ready to divide in two *,
and the cleft was the origin of two fingers.
“ In two or three days, I remarked a new cleft at
the upper extremity of the papilla, which was the be¬
ginning of a new finger: the third, in its turn, appeared
on the 19th. The conical papilla had then difappear-
ed ; and in its place was feen a final] open hand with
four fingers, ft ill very minute, but quite well (haped.
“ On the 3d of Auguft, the cone began to divide,
that is, two fingers became evident.
“ On the glh, a hand extremely minute, but the moft
beautilui objeft imaginable, was obferved at the ex¬
tremity of the arm. The fingers, all of unequal length,
were diftinguilhed, the fmalleft being juft perceptible.
The trunk, or part of the original arm, connected to the
body, may be reeognifed by the brown colour, and
from being covered with white points. The new arm
is of a lighter and uniform colour. Four fingers of the
hand are vifible: the largeft not above half a line in
length.
“ The hand of the left arm had made confiderable
progrefson the 21ft : it had expanded, and nearly ac¬
quired the figure peculiar to the newt’s hand. The
fingers alfo had extended, and become thicker in pro¬
portion. The whole hand began to colour, and brown
fpecks were diftinguilhable on different parts; they
were more evident on the back of the hand than on
the fingers.
“ On the 21 ft, the hand has already affumed its na¬
tural ihape, and the rapid progrefs of evolution is fuf-
pended. Colouring of the arm begins near the trunk :
but all the xeft is of a mixed gray and violet colour.
f I hough 1 have not hitherto exprefsly faid fo, it
will obvioufiy be prefumed, that there is a kind offemi-
tranfparency in the reproduced parts, which the origi¬
nal members have not, d'his continues long, and changes
llowly as the reproduftions colour. The tranfpa-
rency is evidently greater on the edges of the fingers
than elfewhere j if examined with a magnifier, they feem
mclofed in a fine diaphanous envelope : but nothing of
this is evident in the old fingers. Parts beginning to
unfold naturally have a degree of tranfpareneywvanting
in thofe further advanced, or fully expanded, becaufe,
with the progrefs of evolution, the calibre of the veffels
increafes, which allows admiffion to more grofs and co-
louiing particles. Whitenefs and tranfparence appa¬
rently coaftitute the primitive ftate of organic bodies.
yfioiogy. Leg, 4 lines-,
-w—' Longeft finger, 34
Longeft toe, 4^-
O L O L Y. 31-
It is this primitive ftate which we defign by the word Phyfiology.
germ ; and w hich we can comprehend, when the orga- u““,'v ~ f
nic whole is expanded to a certain extent. But there
is here a term beyond which wre cannot afeend j for the
organic whole either becomes fo minute or fo tranfpa-
rent, that it efcapes all refearch and our moft perfedt
inftruments.
“ The dimenfions of the old and new members, in
length, were as follows, on the 2d of September.
Old Members.
New Members,
Arm, 3|- lines, Arm, 2^.
Cubit, 3f Cubit, 2|
Longeft finger, Longeft finger, i4-fezW.ii.37*,
“ Experiment.—The tail of a newt amputated tranf-
verfely. Something important would have been want¬
ing, had I negledted amputation of the tail, which is a
very intricate great organic fubitance. It is formed of
a feries of minute vertebrae, with arteries, veins, and
nerves; and it is covered with mufcles and flefli.
“ The tail of a large newt is more than two inches
long, and about half an inch thick, formed like an oar,
and terminated by a foft point. Much might be faid
of the figure, proportions, and pofition of this organ,
and with refpedt to the fundtions it has to exercife j but
thefe would be details foreign to any purpofe : I only
mean to confirm what Sig. Spallanzani has advanced
concerning the admirable reprodudlion of the mem¬
bers.
“ When the tails of large newTs were amputated near
the origin, I never fucceeded in obtaining reprodudlion 5
the whole died in a certain time y and for feveral wrecks
preceding death, a kind of whitilh cotton mould grew
on the wounds, the filaments of which were feveral lines
in length. Neverthelefs, I cannot think that this af-
fedted the animal’s life, for I had feen fimilar mould, or
cottony filaments, on wounds occafioned by amputating
the arms and legs. Thefe filaments gradually difap-
peared, and unequivocal figns’of reprodudtion foon be¬
came vifible. Thus a good obfervation was never ob¬
tained, unlefs the tail was divided about the middle,
and by a fedtion perpendicular to the axis,; A ftreara
of blood, as thick as a hog’s briflle, always fpouted from
the wound. The large veffel, from w'hich it flows, is
fituated near the vertebrae, and its orifice is vifible by-
the naked eye y it immediately elofes y and the orifice
is diftinguithed by a reddifti or brownifh point.
“ The tail of newts is very fenfible, which is particu¬
larly evident in the flendereft part. A portion cut off
will retain life, and move whole hours j and when life
feems entirely extindf, we have only to prick the point-
ed extremity, that motion may be renewed; it rifesand
falls alternately, and with greater force, according to
the period that has elapfed finee the operation. The
motion of this feparated part bears great refemblance
to that which is peculiar to certain apodal worms; it iV
undulatory, and evidently depends on irritability, which
is extremely aftive in fo mufcular an organ.
“ Immediately after the operation, the area of the cut
exhibits a very long ellipfe; the two extremities almoft
terminating in a point. The fmalleft diameter is a-
bout a line acrofs, and the largeft five or fix. In the
centre are the vertebrae, or biood-veffels ; the reft o£
the area feems full of Lnall oblong dear white fub-
fiance^ -