ties are several

and first, the blood of the Chama

leon is of a violet blue, which colour it will preserve for some minutes on linen or paper, especially on such as have been steeped in alum-water. In the second place, the different tunicles of the vessels are yellow, as well in their trunks as in their ramifications. The epidermis, or exterior skin, when separated from the other, is transparent, without any colour; and the second skin is yellow, as well as all the little vessels that touch it. Hence it is probable that the change of colour depends upon the mixture of blue and yellow, from which result different shades of green.

Thus, when the animal, healthy, and well fed, is provoked, its blood is carried in greater abundance from the heart towards the extremities, and, swelling the vessels that are spread over the skin, its blue colour subsides the yellow of the vessels, and produces a blue green that is seen through the epidermis. When, on the contrary, the animal is impoverished and deprived of free air, the exterior vessels being emptier, their colour prevails, and the animal becomes a yellow-green till it recovers its liberty, is well nourished, and without pain, when it regains the colour; this being the consequence of an equilibrium in the liquids, and of a due proportion of them in the vessels *.

Hasselquist says, that he never observed the Chamæleon assume the colour of an external object presented to its view, although he made several experiments for the purpose. He says its natural

* D'Obsonville, 35

colour is an iron grey, or black mixed with a little grey. This it sometimes changes, and becomes entirely of a brimstone-yellow, which, except the former, is the colour it most frequently assumes. It sometimes takes a darker or greenish yellow, and sometimes a lighter. He did not observe it assume any other colours, such as blue, red, purple, &c. When changing from black to yellow, the soles of its feet, its head, and the bag under its throat, were the first tinged, and then by degrees that colour spread over the rest of the body. He several times saw it marked with large spots of both colours all over its body, which gave it an elegant appearance. When it became of an iron grey it dilated its skin, and became plump and handsome; but as soon as it turned yellow, it contracted itself, and appeared empty, lean and ugly and the nearer it approached. in colour to white, the more empty and ugly it appeared; but its shape was always the most unpleasant when it was speckled. Mr. Hasselquist kept a Chamæleon for near a month; it was during the whole time very nimble and lively, climbing up and down its cage, fond of being near the light, and constantly rolling about its large eyes. It took no food during the whole of this time, so that at last it became lean, and evidently suffered from hunger. It could no longer hold fast by the grating of the cage, but fell through weakness, when a turtle that was in the same room bit it and hastened its death. From its being able to support long abstinence the

vulgar notion has arisen of the Chamæleon's living only on air *.

When the Chamæleon is removed from its place, Dr. Russel also informs us that it does not immediately change colour, nor does it constantly in changing assume that of the ground upon which it is laid. Thus, if put into a box lined with white, or with black, it will sometimes in the black become of a lighter colour than before, and vice versa; and sometimes will assume a brimstone colour. When the experiment was made upon a cloth of various colours, but where the animal had a larger field to move about, the event was the same.

It frequently goes through a fuccession of colours before taking that of the body nearest it. When Jaid on the grafs, it will perhaps, from a light earthy colour, first become darker, then black, yellow, again darkish, and last of all green. At other times it becomes green at once; and so of other colours when laid on other grounds: whence it was hastily believed that the transition was always sudden. But, notwithstanding this irregularity in its change, especially when hurried or disturbed, its most permanent colour in repose was that of the ground on which it lay, provided the ground was not of one of the colours that it never does assume, of red or blue. Little material difference was observable, whether the experiments were made in the shade or

* Hasselquist, 217.

in the sun; but the animal appears duller at some times than at others, and captivity seems to abate its alacrity in changing*.

Mr. Barrow says that " previous to the Chamæ leon's assuming a change of colour, it makes a long inspiration, the body swelling out to twice its usual size; and, as this inflation subsides, the change of colour gradually takes place. The only permanent marks are two small dark lines passing along the sides +."

OFFICINAL SCINK ‡.

This species of Lizard, which is generally six or seven inches in length, is found in great numbers in the sandy plains of Egypt, Libya, Syria and Arabia.

The head is not very large, scarcely thicker than the neck. The body is cylindrical, and the tail not long, and ending in a compressed tip. The body is covered with small scales, and is of a pale yellowish brown colour, with a few broad, dusky, transverse bands. The scales lie so close as to give the surface a glossy or oily appearance.

In its manners this little animal is exceedingly

*Russel's Natural History of Aleppo.

+ Barrow's Travels in Africa.

SYNONYMS.-Lacerta Scincus. Linn.-El Adda. Bruce. Common Scink. Officinal Scink. Shaw. Shaw's Gen. Zool. vol. 3. tab. 79.

harmless, supporting itself principally on insects. Mr. Bruce says that it burrows in the sand, and performs this operation so quickly, that it is out of sight in an instant, and appears rather to have found a hole than to have made one. It often comes out in the heat of the day to bask in the sun; and, if not very much frightened, will take refuge behind stones, or in the withered ragged roots of the Absynthium, dried in the sun to nearly its own colour. It runs with very great celerity.

This is one of the few Lizards which the Arabs in all times have believed to be free from poisonous qualities, and yet to have all the medical virtues so abundantly lavished upon the more noxious species. It was in high estimation in Europe, as well as in the eastern climates, as a valuable article in the Materia Medica. It is not however at present considered here as of any importance, and even amongst the Arabs its character is greatly on the decline.

This, and others of the Lizard tribe, are so numerous in the East, that Mr. Bruce is positive the number he one day saw in the great court of the temple of the Sun at Balbec amounted to several thousands. The ground, the walls and stones of the ruined buildings were covered with them; and their various colours made a very extraordinary appearance, from their glittering under the sun, in which the animals lay sleeping and basking.