32 



ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 39 



Orthoptera 



Cockroaches, 

 Grasshoppers, 

 Crickets, and 

 Their Allies 



Insects usually with two pairs of wings, each 

 with a very fine, dense network of veins, the 

 front pair thick and leathery, the hind pair 

 delicate and fanlike. Mouthparts fitted for 

 chewing, with stout mandibles. The young 

 look and act like the adults but do not have 



wings. Terrestrial insects. This order in- 

 cludes all the cockroaches, praying man- 



tids, walking sticks, grasshoppers, crickets, 



and katydids. Fig. 20 shows a native wood 



cockroach, Parcoblatta pennsylvanica (De 



Geer) ; fig. 21 shows the migratory locust 



or grasshopper, Melanoplus mexicanus 



(Saussure). Several 



Of the groups Of Or- Fig. 20. — Orthoptera. 



,ii i j m. Parcoblatta pennsylvan- 



thoptera have adults ic(tj one of 4 e common 



that never develop wood cockroaches. Ac- 

 wings. These include ££ length about °- 8 

 such odd forms as 



Fig. 21. — Orthoptera. Melanoplus mexicanus, the migratory locust, a com- 

 mon Illinois grasshopper. Actual length about 1.0 inch. 



Fig. 22. — Orthoptera. Ceuthophilus maculatus, a wingless cave cricket. 

 Crickets of this kind are found in caves, under rocks, and in basements. 

 Actual length about 1.0 inch. 



