138 THE COLOURS OF ANIMALS 



the appearance of the gilded form of the Small 

 Tortoiseshell chrysahs, viz. by a gilt and by a white 

 environment. 



The chrysalis of the Red Admiral Butterfly 

 {Vanessa Atalanta) has no green variety, but it appears, 

 like the Small Tortoiseshell, as a dark or a glittering 

 form resembling the two conditions of rock-surfaces 

 upon which it often pupates, hanging suspended 

 without any attempt at concealment except such as is 

 afforded by its very perfect colour-harmony with the 

 surroundings. I have shown that this species also is 

 susceptible, and that either variety of pupa is produced 

 by the appropriate environment. But this chrysalis 

 is very commonly found attached to the food-plant, 

 and when this is the case it hangs suspended in a 

 tent formed of leaves carefully spun together by the 

 caterpillar, so that it is concealed from view. The 

 larva also often has the habit of partially biting 

 through the leaf-stalk or stem, so that the leaves of 

 its retreat hang down and wither. The dead brown 

 leaver thus afford a far more harmonious background 

 for the dark pupa, if by any chance it becomes 

 exposed to view. 



The Small Tortoiseshell has neither the green 

 variety of the Peacock nor the protective habit of 

 the Eed Admiral, and therefore it almost invariably 

 seeks mineral surroundings for the pupal period, and 

 very rarely becomes a chrysalis on its food-plant. 

 In 1886 I only found three such pupae suspended to 



