116 INSECTS INJURIOUS TO VEGETATION. 



tradistinction to the far greater changes exhibited by those insects 

 which pass through a complete transformation in their progress to 

 maturity. 



Cockroaches are general feeders, and nothing comes amiss to 

 them, whether of vegetable or animal nature ; the Mantes or 

 soothsayers are predaceous and carnivorous, devouring weaker 

 insects, and even those of their own kind occasionally ; but by 

 far the greater part of the Orthopterous insects subsist on vegeta- 

 ble food, grass, flowers, fruits, the leaves, and even the bark of 

 trees: whence it follows, in connexion with their considerable 

 size, their great voracity, and the immense troops or swarms in 

 which they too often appear, that they are capable of doing great 

 injury to vegetation. 



The Orthoptera may be divided into four large groups r 



1. Runners (Orthoptera cursoria*)., including earwigs and 

 cockroaches, with all the legs fitted for rapid motion ; 



2. Graspers {Orthoptera raptoria), such as the Mantes, or 

 soothsayers, with the shanks of the fore-legs capable of being 

 doubled upon the under-side of the thigh, which, moreover, is 

 armed with teeth, and thus forms an instrument for seizing and 

 holding their prey ; 



3. Walkers (Orthoptera ambulatoria) , like the spectres or 

 walking-sticks, having weak and slender legs, which do not admit 

 of rapid motion ; and 



4. Jumpers (Orthoptera saltatoria), such as crickets, grass- 

 hoppers, and locusts, in which the thighs of the hind-legs are 

 much larger than the others, and are filled and moved with power- 

 ful muscles, which enable these insects to leap with facility. 



I. RUNNERS. (Orthoptera Cursoria.) 



In English works on gardening, earwigs are reckoned among 

 obnoxious insects, various remedies are suggested to banish them 

 from the garden, and even traps and other devices are described 

 for capturing and destroying them. These little insects have got 

 a bad name, whether deservedly or not, has never appeared ; and, 



* These are the four divisions proposed by Mr. Westwood in his " Introduc- 

 tion," who, however, applies to them their Latin names only. 



