44 TRUE TALES OF THE INSECTS. 



part of the wing. Beneath it the wing is folded longi- 

 tudinally in a complicated fan- like manner, and reposes 

 on the back ; and seeing the narrow condition of the 

 body, this coriaceous sheath-like portion must be narrow 

 too, in order to adapt itself to the surface of the abdomen. 

 It looks as if it were really a tegmen ; moreover, this 

 appearance is enhanced by the fact, that it is often quite 

 differently coloured from the rest of the organ. In some 

 species it is green, like the short wing-covers, whilst 

 the other part of the wing is pink. Among many, 

 however, both organs of flight exist in a more or less 

 rudimentary state (see Fig. 17), and many more remain 

 throughout their lives without ever acquiring wings or 

 wing- covers. 



The antennae are very variable ; and the same remark 

 applies to the colour of the body in many Phasmidae, 

 which may change from brown in early life, to green, 

 subsequently returning to the brown tint. If this be 

 owing to the presence of chlorophyll or other plant- 

 juices among the insect-tissues, its explanation is not far 

 to seek. 



Characteristics and Habits. 



Chiefly inhabitants of tropical countries, these insects 

 are extremely sensitive to cold ; the occurrence of frost 

 puts an end to their existence. They live on vegetation, 



