56 



THE STUDY OF INSECTS 

 Family Locustid/£* 



The Locusts or Short-honied Grasshoppers 



The family Locustida? includes the locusts or short-horned grass- 

 hoppers. These are common and well-known insects. The antennas are 

 much shorter than the body, and consist of not more than twenty-five 

 segments. The ovipositor of the female is short and composed of separate 

 plates; and the basal segment of the abdomen is furnished on each side 

 with a tympanum, the external parts of the organs of hearing (Fig. 94). 



It is to these insects that the term locust is properly applied; for the 

 locusts of which we read in the Bible, and in other books published in 

 the older countries, are members of this family. Unfortunately, in the 

 United States the term locust has been applied to the Periodical Cicada, 

 a member of the order Homoptera, described later. 



Locusts lay their eggs in oval masses and cover them with a tough 



Fig. 94. — Side view of Locust with wings removed to show 

 ear. See the arrow. 



Fig. 95. 



brum. 



Mclanoplus femur-ru- 



substance. Some species lay their eggs in the ground. The female makes 

 a hole in the ground with her ovipositor, which is a good digging-tool. 

 Some species even make holes in fence-rails, logs, and stumps; then, 

 after the eggs are laid, the hole is covered up with a plug of gummy 

 materials. There is but one generation a year, and in most cases the 

 winter is passed in the egg-state. This family is of great economic im- 

 portance, as the members of it usually appear in great numbers in every 

 region where plants grow, and often do much damage. 



The males of many locusts are able to produce sounds. This is done 

 in two ways: first, certain species rub the inner surface of the hind 

 femora, upon which there is a row of minute spines, against the outer 

 surface of the wing-covers. In this case each wing-cover serves as a 

 fiddle, and each hindleg as a fiddle-bow. Second, other species rub to- 

 gether the upper surface of the front edge of the hind-wings and the 

 under surface of the wing-covers. This is done while the locust is flying 

 and the result is a crackling sound. 



There are very many species of locusts in the United States. We 

 have space to refer to only a few here. 



The most familiar member of the family is the red-legged locust, 

 Mclanoplus femur-ruhrum (Fig. 95). It is more abundant than any 

 other species throughout the United States, except in the high dry lands 

 of the central part of the continent where the Rocky Mountain locust, 

 Melanoplus sprctus, has its breeding grounds. 



The Rocky Mountain locust is only about one to one and a quarter 



* This family is termed the Acrididas by some writers, other writers use the fam- 

 ily name Acridiidaj. 



