The Grasshopper 



353 



In America the Rocky Mountain Locust is the one which does the 

 great damage to crops. The exact time of laying and hatching eggs 

 varies somewhat with the region of the country. 



Often the young, until after the second or third molt, content them- 

 selves with feeding on whatever food is close at hand, but as soon as 

 this food becomes scarce, the animals congregate and, as Ealand says, 

 they march across the country in solid bodies, sometimes as much as a 

 mile wide, "devouring every green crop and weed as they go. During 

 cold or damp weather and at night they collect under rubbish, in stools 

 of grass, etc., and at such times almost seem to have disappeared ; but 

 a few hours of sunshine brings them forth as voracious as ever. When, 

 on account of the immense numbers assembled together, it becomes 

 impossible for all to obtain green food, the unfortunate ones first clean 



out the underbrush and then 

 feed upon the dead leaves and 

 bark of timber lands, and have 

 often been known to gnaw 

 fences and frame buildings. 

 Stories of their incredible ap- 

 petites are legion. A friend 

 informs the author that he still 

 possesses a rawhide whip 

 which they quite noticeably 

 gnawed in a single night. 



"By mathematical compu- 

 tation it has been shown that 

 such a swarm could not reach 

 a point over thirty miles from 

 its birthplace, and as a matter 

 of fact they have never been known to proceed over ten miles." 



There are other species and genera which do not migrate from their 

 native haunts. Many ingenious ways have been used to exterminate 

 them. Certain fungus growths on plants, which the grasshopper uses 

 for food, are fatal to him. So, too, is the little tachina fly already men- 

 tioned. In some regions, agriculturists develop such fungus growth 

 and flies to assist in controlling the injurious insects. 



The effect of a difference of temperature on insects is well illustrated 

 by the fact that there is only one annual generation of grasshoppers in 

 New England while there are two in Missouri. 



Ditches are often dug so that the animals will fall into them, or 

 kerosene emulsion is poured on water standing about, or placed in 

 simple trough-like wooden movable ditches. Even if the grasshopper 

 crawls out of the oil, it dies shortly after. 



For the control of grasshoppers, see any of the books on economic 

 entomology mentioned at the end of Chapter XXIV. 



Fig. 229. Long- and Short-Horned Grasshoppers. 



A. Order Orthoptera. Katydid, Microcentrum 

 retinerve. (From Sedgwick's Zoology, after Riley.) 



B. Red-legged grasshopper (Melanoplus femur- 

 rubrum); Ab, abdomen; Ant, antennae; E, eye; M, 

 mouth; T , thorax; S, spiracles. 



