5<2 
L A C E R T A. 
bones of the jaws denticulated, To as to reprefent fmall 
teeth. The tongue is of a very extraordinary form ; be¬ 
ing compofed of a white folid flefh, about ten lines long, 
and three broad, round, a little flattifh towards the end, 
'hollow, and open, fomewhat like the end of an elephant's 
probofcis. This tongue is fattened to the os hyoidcs by 
means of a fort of trunk, fhaped like an inteftine, fix 
inches long, and a line broad, having a membrane with¬ 
out, and a nervous fubflance within, which is folid and 
compact, though foft, and not ealily divifible into fibres; 
this trunk ferves to call out the tongue, which is fattened 
to it, by extending it, and to draw it back by contract¬ 
ing it, which motion it is enabled to perform by a kind of 
cartilaginous ftylus to which its ir.vefting membrane is 
.attached, and over which it is plaited like a filk flocking 
on the leg: this ftylus-is an inch long, and takes its ori¬ 
gin from the middle of the bafe of the os hyoides, as in 
the tongue of feveral birds ; a number of blood-vefi'els are 
•xiiftributed on the tongue. 
The form, flruCture, and motion, of the eyes, is very 
peculiar; they are very large, viz. above five lines in dia¬ 
meter; -appearing fpherical, projecting in the living ani¬ 
mal full half of their diameter; they are covered with 
•one fingle eyelid or fkin, pierced in the middle with a 
fmall hole of not more than a line in diameter, through 
which the pupil appears, furrounded by a gold-coloured 
.iris ; the eyelid, or inverting lkin, is granulated like the 
■reft of the animal; the fore part of the eye is fattened 
to the lid, fo that the lid follows all the motions of the 
■eye. Seba compares the lid to the fpoked wheel of a 
coach, and the pupil to the nave. This ItruCture refem- 
ble's a good deal the artificial defence employed by the 
Laplanders, and other northern n'ations, for defending 
their eyes againft the exceflive reflection of light from the 
furface of the fnow, by means of a narrow flit in a thin 
piece of wood. Perhaps, inftead of this natural defence 
being intended to preferve the acutenefs of vifion in the 
eyes of the chameleon, it may be the caufe of that pro- 
■perty; as their eyes, lefs fatigued by too ftrong admiltion 
©flight, may thereby acquire greater fenfibility andacute- 
nefs. Betides the above-defcribed Angularity in ftruCture, 
the eyes of the chameleon have another property, which 
feems to belong exclufively to this animal, as well as that 
other circumltance ; they are each moveable independent 
of the other, fo that one eye fometimes looks forward, 
while the other is turned backward ; or one looks up, 
while the other fees fuch things as are below. Its feet 
are by no means fitted to ferve as oars for fwimming, but 
they are admirably adapted for keeping fall hold of the 
branches of trees and rtirubs which it frequents in fearch 
of food. It is able to grafp thefe branches, holding one 
of the bundles of toes forward and the other behind, or 
one on each fide, as is done by woodpeckers, cuckows, 
parrots, and other birds, which enables it to fix itfelf very 
firmly. In walking on the ground, however, this confor¬ 
mation by no means affords a firm fupport; hence it keeps 
almoft continually on trees. In this it is farther aflifted 
by the nature of its tail, which is long and prehenfile, like 
that of the fapajous, (fee Simia bulzebul,) and is very 
ftrong ; being enabled to lap it round the branches, with 
confiderable force, it may be faid to ufe it as a fifth hand 
or paw, to prevent it from falling, and to aflift in pafling, 
with greater eafe and fafety, from one branch to another. 
Belon informs us, that the hedges in the gardens near 
Cairo, efpecially along the banks of the Nile, contain 
great numbers of chameleons, which, he alleges, keep in 
that fituation, on purpofe to avoid the vipers and ceraftes, 
which fwallow them whole when they can get hold of 
them. They are not, however, fafe from the ichneumon, 
or from birds of prey, even in thefe hedges, for their mo¬ 
tions are extremely flow, in travelling from one branch to 
other ; fo that they may rather be faid to lie in ambufh 
under the leaves, to catch fuch infedts as may alight on, 
or come within reach of, its adhefive tongue, than to go 
in fearch of prej^. The quicknefs with which the chame¬ 
leon feizes infects, renders it ufeful to the Indians, who 
are rejoiced to fee this otherwife innocent animal in their 
houfes. Its manners are fo very gentle, that, according 
to Profper Alpinus, a perfon may pulh the finger into 
its mouth, and it makes no attempt to bite. 
Whether climbing flowly along the branches of trees, 
or concealing itfelf below the leaves in expectation of in- 
fefls, or walking deliberately on the ground, the chame¬ 
leon is always extremely ugly in its appearance, having 
neither agreeable proportions, nor beauty of form, nor 
elegant movements, to pleafe the eye of the obferver; fo 
that no one can attempt to catch, or even to touch, it 
without difguft. When walking on the ground, it llep* 
forward in a cautious groping manner, never lifting one 
foot until well afl'ured of the firmnefs of all the others. 
In confequence of thefe precautions, its motions have a 
ridiculous appearance of gravity, when contrafted with 
the fmallnefs of its iize, and the activity one would expeCt 
to find in an animal fo fimilar to thofe lizards that move 
about with fo much quicknefs. Thus, this animal, which 
is fo interelling to naturalifts, by the lingular covering 
and mobility of its eyes, by the form and ItruCture of its 
feet and tail, and by almolt every circumltance in its 
figure, manners, and habits, feems only calculated to ex¬ 
cite difguft or contempt in Superficial obfervers; and, but 
for its very extraordinary property of prefenting a variety 
of changing colours, according to. circumltances, which 
has attracted a very marked attention, it would never have 
become the favourite object of fo many poets, and the 
common allufion of almolt the whole world. See fig. io. 
That it depended in a very confiderable degree on the 
will of the animal to exert this power, was too apparent 
to be denied ; but in what manner this effeCt was pro¬ 
duced, and operated on the frame of the chameleon, wasre- 
l’erved for the inveftigations of later naturalifts to deter¬ 
mine with competent accuracy. Seneca maintained it 
was effected by fuffufion ; Solinus, by reflection ; and 
others, as the Cartefians, by the different difpofition of 
the parts that compofe the lkin, which give a different 
modification to the rays of light. Kircher aferibes the 
change of colour in the chameleon to the power of ima¬ 
gination in the animal, becaufe it lofes it when dead. Dr. 
Goddard attributes it to the grains in the lkin ; which, in 
the feveral poftures, he thinks, may fhow feveral colours, 
and, when the creature is in full vigour, may have, as he 
terms it, rationem Jpeculi, or the effeCt of mirrors, and re¬ 
flect the colours of the bodies adjacent. That the colours 
are not by any means determined by furrounding objeCts, 
has been the aim of late obfervers to demonftrate; that 
they change with frequency and rapidity is admitted, but 
it is not true that they are influenced by the colour of 
any objeCt in contaCt with it. The changes of colour 
which this animal exhibits vary according to the ftate of 
its health, the temperature of the weather, the age or fex, 
and a variety of other fubordinate circumltances, all which 
tend to operate a change in the variable afpeft of this lin¬ 
gular creature. Thefe tranlitions confiit chiefly in the 
alteration of the lhades from the natural green or bluifli- 
grey of the lkin into pale yellowifli with irregular fpots 
and variegations of dull red; or dulky inclining to 
blackilh. The epidermis of this animal is tranfparent, 
the lkin beneath yellow', and the blood of a lively violet 
blue. The tranfitory combination of thofe colours there¬ 
fore becomes apparent externally when the blood of the 
heart is impelled to the furface of the lkin and the extre¬ 
mities, changing to violet, yellow, blue, and green, in a 
variety of hues, as the blood circulates near the fuperficies. 
When the animal is fick, it turns to a greyifh dirty yellow, 
or brownifli, like a decayed leaf, this being the true co¬ 
lour of the lkin when the blood is withdrawn ; but, expofe 
it to the rays of the fun, the genial heat revives and in¬ 
vigorates the whole fyftem, and, fetting the blood, before 
torpid, in motion towards the lkin, the violet and bluifh 
prevail 
i 
