78 INJURIOUS AND USEFUL INSECTS 



The ground-colour is usually a dark grey, diversified by 

 reddish warts, as well as by longitudinal streaks of white and 

 black. Brushes of variously coloured hairs stand out from 

 the body. A little behind the head is a pair of long black 

 pencils, which point forwards. Four segments near the 

 middle of the body bear shorter tufts of white hairs, standing 

 erect on the middle of the back ; from the sides of the two 

 foremost of these four segments lateral pencils project, the 

 first pair being tawny, the second black. A long black pencil 

 points backwards from the end of the body, and forms a kind 

 of tail. Professor Poulton tells us that "a caterpillar of the 

 common vapourer moth {Orgyia antiqua) was introduced into 

 a lizard's cage, and when attacked, instantly assumed the 

 defensive attitude, with the head tucked in and the ' tussocks ' 

 separated and rendered as prominent as possible. An unwary 

 lizard seized the apparently convenient projection ; most of 

 the ' tussock ' came out in its mouth, and the caterpillar was 

 not troubled further. The lizard spent a long and evidently 

 most uncomfortable time in trying to get rid of its mouthful 

 of hairs."* 



When full-fed, the larvae spin whitish cocoons, interwoven 

 with many of their own cast hairs, and change to pupae. In a 

 few days the moths emerge, and then a striking difference in 

 the outward form of the sexes is remarked. The male moth 

 has rather broad, tawny wings, each marked with a con- 

 spicuous whitish spot. His feelers are comb-like, with a 

 double row of fine and close-set projections. Their large size 

 and complex structure indicate that they are the seat of a 

 well developed organ of special sense. The male moth flies 

 fast, hovering in the sunshine, and describing a series of 

 loops as he makes his way from garden to garden. He may 

 often be seen in the squares, and even in the streets of 

 London, where the caterpillars abound in the shrubberies. 

 This mode of flight our forefathers seem to have called 

 vapouring: hence the name which they gave to the moth. 

 The female is so different that no one could have guessed 

 that she was of the same species. Her body is covered with 

 tawny hairs, the abdomen egg-shaped, and far too heavy for 

 the short and weak legs. She has no wings that appear, and 

 it is only by close examination that we discover their useless 



* " The Colours of Animals," pp. 197-8. 



