110 



ORTHOPTERA. 



tenus femui'-7'uhriiin. The ravages of this insect in 

 the West are described in the First, Second, and Third 

 Reports of the United States Entomological Commis- 

 sion, 1877-83. 



The little grouse locust, Tettix (Fig. 61, enlarged), 

 belonging to this family, is 

 very instructive. The pro- 

 thorax (^') has grown back- 

 ward, and taken upon itself 

 the work of the wing-covers, 

 and these being no longer 

 needed, have become reduced 

 to mere scales {tv^). The 

 second pair of wings (7<:/") is 

 seen projecting beyond the 

 prothoracic cover. 



Most Orthoptera are ter- 

 restrial, both in the lar\^al and 

 adult condition, and are sub- 

 ject to similar physical surroundings. They take food 

 in a solid form, and the majority are vegetable eaters, 

 and have to hunt for a living throughout Hfe. This 

 similarity in habits and habitats is correlated with a 

 corresponding similarity in structure and development. 

 The larvae are, as a rule, active feeders, resembling 

 their own adults or imagos quite closely in this re- 

 spect, and do not have to go through with any very 

 marked changes during their growth. 



We have seen that the cockroaches have special- 

 ized modes of protecting the eggs and young in 

 sacs and are exclusively terrestrial ; nevertheless, in 

 these, which are the most generalized forms, the Thy- 



Fig. 61. 



