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reports; for, according to their experience, when the 

 animal takes other colours than gray, and disguises itself 

 to appear in masquerade, as ^lian pleasantly observes, it 

 covers only certain parts of the body with them. They, 

 finally, laid their chameleon on substances of various 

 colours, and wrapped it up in them ; but it did not take 

 those colours as it had taken the white, and, indeed, they 

 allow that it only took the white the first time the ex- 

 periment was made, though it was repeated several times 

 and on different days. 



Hasselquist's experiments with regard to the mutability 

 of colour were followed by nearly the same consequences 

 as mine ; but he thought that the changes depended on 

 a sort of disease, a kind of jaundice, to which the animal 

 was subject, particularly when it was irritated. 



The blood, in the opinion of M. d'Obsonville, was the 

 cause of the change. That fluid, according to him, is, in 

 the chameleon, of a violet blue, which colour, he says, it 

 will retain on linen or paper for some minutes, if it be 

 previously steeped in a solution of alum. The coats of 

 the blood-vessels he found to be yellow, both in their 

 main trunks and ramifications, and he comes to the con- 

 clusion that green will be the product. Like Hassel- 

 quist, he attributes the change of colour to the passions 

 of the creature. He holds that, when a healthy chame- 

 leon is provoked, the circulation is accelerated, the vessels 

 spread over the skin distended, and so a superficial blue- 

 green colour is produced ; but when the animal is shut 

 up, deprived of free air and impoverished, the circulation 

 becomes sluggish, the vessels are not well filled, and the 

 languid chameleon changes to a yellow-green, which con- 

 tinues during its imprisonment. 



Others, the late Sir John Barrow for instance, have 

 observed that, previous to a change, the chameleon makes 

 a long inspiration, when the body is inflated so as to 

 appear twice its usual size, and as the inflation subsides, 



