CHAMELEONS. 529 



the chameleon brings both of its eyes to bear upon the object. " Not- 

 withstanding," says Weissenbaum, " the strictly symmetrical con- 

 struction of the chameleon as to its two halves, the eyes move inde- 

 pendently of each other, and convey different impressions to the 

 different centres of perception : the consequence is that, when the ani- 

 mal is agitated, its movements appear like those of two animals glued 

 together. Each half wishes to move its own way, and there is no 

 concert of action. The chameleon, therefore, is not able to swim like 

 other animals ; it is so frightened when put into water that the faculty 

 of concentration is lost, and it tumbles about as if in a state of intoxi- 

 cation. Nay, more, the chameleon may be asleep on one side and 

 awake on the other." 



The chameleon is often seen to inhale air, gulp after gulp, with 

 great avidity, thus inflating its body enormously, even to the feel; and 

 tail. As has been already stated, the animal's lungs are very large 

 so large, indeed, that it was supposed by Pliny (who simply transcribes 

 the accounts given by Greek authors) that the lungs almost filled the 

 entire cavity of the body; these lungs connect with the air-cells be- 

 neath the skin. By taking air into the lungs, whence it passes into 

 the air-cells, the chameleon is able to inflate itself to as much as twice 

 its ordinary size ; and often it remains so inflated for a long time, 

 now slightly collapsing, again swelling out, till the skin becomes as 

 tense as the head of a drum. No doubt it was this power of self-infla- 

 tion which led the ancients to suppose that, " alone among animals, 

 the chameleon neither eats nor drinks, its only sustenance being air." 

 -{Pliny.) 



But the color-changes of the chameleon form perhaps the most in- 

 teresting phenomenon connected with this animal. We need not 

 repeat the fabulous stories told about these color-changes : the facts 

 which can be strictly verified by direct observation are wonderful 

 enough without the adornments of imagination. These changes of 

 color range from whity-yellow, through yellow, bright and dark green, 

 to dull black ; and these diversities of coloration may afiect the entire 

 surface of the animal, or one or other of its sides, or may appear only 

 in spots. "When the chameleon is asleep, and not exposed to the 

 direct rays of the sun, its color is a whity-yellow ; when basking hi 

 the sun, it is a dingy black or dusky brown. On being aroused from 

 sleep, the side which is first awakened assumes a darker shade. There 

 is reason for believing that sunlight, apart from the warmth which 

 accompanies it, is very grateful to the chameleon, and, in response to 

 this stimulus, he at once begins his play of color. M. Paul Bert, a 

 French savant, whose name is familiar to the readers of The Popular 

 Science Monthly, has for some time been engaged in studying the 

 anatomy and mechanism of these phenomena. His researches are not 

 yet completed, but we may state some of the facts which he has estab- 

 lished. 



VOL. vi. 34 



