24 GENERAL ZOOLOGY 



unwary visitors as do not detect the imposition. In this case 

 the resemblance is to an object attractive to the prey, and 

 may be spoken of as alluring coloration. Dr. J. Anderson 

 showed specimens of one of these insects to members of the 

 Asiatic Society of Bengal in 1877, and communicated infor- 

 mation concerning them as follows. " On looking at the 

 insects from above, they did not exhibit any very striking 

 features beyond the leaf-like expansion of the prothorax and 

 the foliaceous appendages to the limbs, both of which, like 

 the upper surface of the insect, are colored green ; but on 

 turning to the under surface the aspect is entirely different. 

 The leaf-like expansion of the prothorax, instead of being 

 green, is a clear, pale lavender violet, with a faint pink bloom 

 along the edges of the leaf, so that a portion of the insect 

 has the exact appearance of the corolla of a plant, a floral 

 simulation which is perfected by the presence of a dark, black- 

 ish-brown spot in the center over the prothorax, and which 

 mimics the opening to the tube of a corolla. A favorite posi- 

 tion of this insect is to hang head downwards among a mass 

 of green foliage ; and when it does so it generally remains 

 almost motionless, but at intervals evinces a swaying move- 

 ment, as of a flower touched by a gentle breeze." 



Definition of Orthoptera (Gr. orthos, straight; pteron, wing). 

 All the insects mentioned in this chapter have the mouth-parts 

 adapted to biting, and most of them have two pairs of wings. 

 The posterior wings, when present, are folded lengthwise like 

 a fan beneath the hardened anterior wings, and are thus pro- 

 tected from injury. These insects agree in their mode of 

 growth, which is a gradual increase of size by successive molts, 

 without any abrupt change of form. The imagoes differ from 

 the nymphs chiefly by their larger size and the presence of wings. 

 On account of these common characteristics these insects are 

 united in a group, or order, called Ortliop' tera, in allusion to 

 the longitudinal folding of the posterior pair of wings. 



