ORDER VII. ORTHOPTERA. 



The distinguishing characteristics of the Orthoptera ^ 

 or straight-winged insects {6p06s, straight ; wrepov, a 

 wing, p. 29) are already familiar through the study of 

 the locust, but a few of the commonest species remain 

 to be noticed. 



BLATTID.E. 



The cockroach, PeiHplaneta orientalis (PI. IV., Fig. 

 54 $ ; Fig. 559, p. 102), is, pre-eminently, a flattened 

 insect. The wedge-shaped head (^) is bent under, 

 and nearly concealed by the large prothorax (<^') . The 

 thoracic rings (Fig. 55, b\ ^", /5'") are simple and un- 

 consolidated. The rings of the abdomen overlap each 

 other, and are capable of great extension and com- 

 pression, and, indeed, the whole body seems to be 

 able to adapt itself to narrow quarters in crevices. 

 The terminal rings in the abdomen of the female are 

 bent downward, as shown in the drawing, and are 

 coarsely serrated on their edges, quite different from 

 the five segments that precede them. The mode of 

 breathing of the cockroach is somewhat different from 

 that of the locust. The sternal portions of the rings 

 are less yielding than the tergal parts, and therefore 

 the latter rise and fall more appreciably. Plateau ^ gives 



1 See also remarks on pp. 110-112. 



2 Miall and Denny, The Cockroach, pp. 161, 162. 



