Chabieleons.- 



-REPTILES.- 



-CHA5IELE0SS. 



33 



its upward gaze ; presently a fly appears, one eye 

 rapidly and interestedly follows all its movements, 

 while the other leisurely glances hither and thither, or 

 remains steady. Accustomed as we are to see in 

 almost all animals the two eyes move in unison, this 

 want of S3'nipathy produces an eiJect most singular and 

 even ludicrous." The Chameleons have a very large 

 mouth. When shut, it is closed so exactly that we 

 can scarcely distinguish the line which indicates the 

 separation of the jaws, though in reality it is deeply 

 cleft. The teeth are sharp-cutting, with three lohes, 

 forming a single line or series upon the sharp edge of 

 each jaw. There are none on the palate. The tongue, 

 however, is the most extraordinarj' organ in the body, 

 and indeed, as a piece of meclianism, is unique. In a 

 state of repose, and when contained in the mouth, it 

 forms a round fleshy tubercle, white and solid, about 

 ten lines long, three in breadth, a little flattened at its 

 extremity, and lubricated with a glutinous secretion. 

 When, however, it wishes to catch its prey, or to 

 quench its thirst with a drop of water, it can launch 

 it out from its mouth with extreme rapidity, and to 

 a distance as great at least as the length of its whole 

 body. When thus protruded, we then see that nine- 

 tenths of its extent consist of a flesliy tube which is 

 hollow, and possessed of such great contractility that 

 it can be withdrawn with great celerity into the mouth 

 again, folding in upon itself, somewhat in the way a 

 pocket telescope is shut up. This motion is performed 

 without making the slightest noise, and in the twinkling 

 of an eye, without any change in the position of any 

 other part of the body. Some portions of the internal 

 structure of these animals, are no less singular than 

 those of the external characters just mentioned. The 

 lungs, for instance, deserve a moment's consideration. 

 When empty, they sink down below the heart, like 

 two small fleshy masses ; but as soon as air penetrates 

 them, the}' swell out so much that they cover the 

 wliole of the intestines, and are too voluminous to be 

 contained even within the abdominal cavity. They 

 are divided into seven or eight lobes or appendages on 

 each side, which terminate in points, and these pene^ 

 trate into the various parts of the abdominal cavity, 

 and into the hollows or vacant places already mentioned 

 in the skin under the muscles. Tliey thus appear to 

 be more or less directly connected with that remark- 

 able property these animals possess of changing tlie 

 colour of their skin. This propert}', as we have seen, 

 in treating of the Agamas (page 29), is not peculiar 

 to the Chameleons ; and besides, though celebrated in 

 fable and in poetry for this faculty, it would appear 

 to be much exaggerated. The commonly received 

 opinion upon the subject is, that the Chameleon 

 assumes the colour of any object upon which it is 

 placed, or which may be presented to it. 



Mr. Martin informs us that numerous living speci- 

 mens of the Chameleon had come under his observa- 

 tion. " To say what is the natural colour of the 

 Chameleon is rather difficult; that which was most 

 permanent in the animals we have seen was a dull 

 j'ellowish, tinged with a livid hue ; the latter pre- 

 vailing more especially on the limbs. Sometimes, 

 however, the universal colour was a straw-yellow. 

 Vol,. II. 



AVhen the animals were teased or irritated, the lungs 

 seemed to empty themselves, the sides collapsed, every 

 rib became visible, and the colour changed to dark 

 livid. When in good health, and enjoying the warmth 

 of the sun to which these animals are very partial, 

 delighting to bask for hours iri the genial rays, the 

 yellow of the skin became changed into a delicate 

 green ; but not always so, for sometimes the skin 

 appeared spotted with yellow upon a dull greenish- 

 gray, and at other times marbled with olive and straw 

 colour. The changes were in general instantaneous, 

 especially from a light to a dark tint; at other times 

 the transition was more slow ; and this was the case, 

 as it appeared to us, when the skin became marbled or 

 mottled. As night came on the tints became more 

 dull, and the general hue was frequently a dusky 

 olive or a dark grayish-brown, not unfrequently tinged 

 with blue." Several observers have noticed the curious 

 fact that sometimes only one side of the animal changed 

 colour. Mr. Slight, in a short account of two Chame- 

 leons which lived for some time in his possession, says 

 that he had often seen one side of a stone colour 

 and the other a black green. Dr. Weissenbom, who 

 had for some montlis a Chameleon in his possession, has 

 also recorded the fact, and attempts to account for it 

 by tlio efl'ect of involuntary galvanic or nervous cur- 

 rents, distinct from each other, independent of each 

 other, and occupying separate halves of the body ; the 

 remote cause being the way in which the light acts 

 upon the animal. Another curious circumstance with 

 regard to the change of colour in this animal, is, that it 

 never assumes a quite white nor a pure red colour. It 

 seems also, from some accounts given us, that it has a 

 strong antipathy to things of a black colour. Forbes, 

 in the " Oriental Memoirs," tells us that one which he 

 kept, uniformly avoided a black board which was hung 

 up in the chamber; and what is more remarkable, when 

 it was forcibly brought before the black board it trem- 

 bled violently and assumed a black colour. Various 

 theories have been promulgated to account for this 

 phenomenon, the change of colour. M. Milne Edwards 

 states that there exist in the skin two layers of colour 

 called pigment. The deeper-seated is of a deep green 

 or violet-red colour, while the superficial layer is of a 

 grayish hue. The deep-seated pigment is contained 

 in branched cavities, and is movable. Sometimes 

 these two appear blended together, while at others, 

 one entirely conceals the other ; and thus by their 

 partial accumulation and var3nng proportions, the 

 changes of colour are produced. In addition to this, 

 Dr. Weissenborn believes that these pigments must 

 possess of themselves the faculty of changing their 

 hues, as no mechanical mixture, he says, of two given 

 colours could produce those various tints which the 

 skin of the Chameleon exhibits at different times. 



THE COMMOlf CHAMELEON iChanieleo vulgaris) is 

 a native of India and Africa. It occurs in Egj'pt and 

 in Northern Africa, and is the species which lias been 

 naturalized in Southern Europe. It has thus, above 

 all others, afibrded opportunities for observation when 

 alive. It is represented with its tongue laundied out, 

 in Plate 3, fig. 2, and Plate 8, fig. 4. This Chameleon 

 was well known to the ancients, who believed it hved 



