Observations on the Chameleon. 537 



which the chameleon exhibits its almost uniform pale colour, 

 as well as those under which it assumes a different hue. 



I. — the colour of the chameleon is of the pale, almost uni- 

 form kind : — 



a. During sleep. (As long as the animal is sleeping, its 

 organism is extremely torpid, its large and thin purse-like ap- 

 pendages contain a considerable quantity of air, which is so 

 slowly deprived of its oxygen, that the process of respiration 

 is interrupted. I have watched the animal in this state ma- 

 ny times, for fifteen minutes or longer, but I have never seen 

 it respire. We may therefore suppose that the rest of the in- 

 voluntary functions are also greatly abolished, in consequence 

 of the nervous currents being extremely weak. When, how- 

 ever, some external agent, as moonlight, artificial light, shak- 

 ing of the room, &c, disturbs the sleep of the chameleon, I 

 have always observed its colour to be different from the nor- 

 mal pale hue. It was then commonly painted with green 

 spots and stripes.) 



b. When the chameleon had been wrapped for some time 

 in flannel, &c, so as to exclude light, ah*, and other stimu- 

 lating agents, and had been left quiet in that state. 



c. When the chameleon had been exposed for a consider- 

 able time to the direct influence of intense sunlight. (Its bo- 

 dy would then always assume the pale yellowish white color, 

 in consequence, no doubt, of the relaxation following the ex- 

 cess of stimulus to which its organism had been exposed. — 

 The animal then looked like a lump of mortar). 



e. When dead.* 



II. — The pale colour is exchanged for other hues under the 

 following circumstances : — 



a. When the animal was taken out of a flannel wrapper, 

 and suddenly exposed to the rays of the sun ; the half turned 

 towards the sun would, within a minute, become bluish black, 

 after having successively exhibited grey, greyish red, drab- 

 violet, and other tints ; whereas the other half, within the 

 time stated, took a deeper colour, but did not advance be- 

 yond greyish brown. (In this experiment the greater activity 



* My specimen died in a rabid fit, which lasted more than twenty-four 

 hours, and during which, though blind, the animal would bite at every ob- 

 ject that came within the reach of its jaws. It would not quit its hold for 

 many minutes. The disease began with cedema of the eyes, and its last 

 form was perhaps developed by my endeavouring to cure the animal with 

 large doses of a solution of phosphorus in sweet oil. The excessive irrita- 

 bility of the chameleon was most strikingly evinced in this last stage. 



