70 TRUE TALES OF THE INSECTS. 



In these wonderful Eastern leaf-insects of the genus 

 Phyllium, it is the female only that so marvellously 

 imitates a green leaf; she alone is possessed of the large 

 leaf-like tegmina. The males of the genus are altogether 

 different from the females ; having instead of the 

 foliaceous tegmina, short wing-covers that are not leaf- 

 like, while the gauzy hind wings, which are particularly 

 large and conspicuous, are totally devoid of leaf-like 

 appearance. 



Tegmen of the Female an Exceptional Structure. 



This disguise of the female in respect of its tegmina 

 is striking to a naturalist from various points of view. 

 He will notice that whereas when there is in insects a 

 difference between the organs of flight of the two sexes, 

 the male has them largest, the very opposite is true of 

 Phyllium ; that is to say, the normal condition is adhered 

 to so far as the hind wings are concerned, but in the 

 front pair the rule is reversed, the leaf-like tegmina of 

 the female exceeding greatly the rudimentary wing- 

 covers of the male. He will also observe as one of the 

 peculiar traits of the family, a trait shown by all other 

 members of the tribe, that the wing-covers or tegmina 

 (when they exist) are greatly abbreviated, even when 

 the wings are largely developed. This is the case in 



