INSECTS AFFECTING GRAINS, GRASSES, FORAGE 95 



farther east. Migrating from their native haunts, flights of 

 the grasshoppers usually reached southern Dakota in early sum- 

 mer, Colorado, Nebraska, Minnesota, Iowa, and western Kansas 

 during midsummer, and southeastern Kansas and Missouri 

 during late summer, appearing at Dallas, Texas, in 1874, and about 

 the middle of October, and even later in 1876. As thus indi- 

 cated, the flights were in a general south to southeasterly direction, 

 while west of the Rockies they descended to the more fertile 

 valleys and plains, but without any such regularity as eastward. 

 While the rate of these flights was variable and entirely dependent 

 upon local weather conditions, twenty miles per day was con- 

 sidered a fair average. The flights were more rapid and more 

 distance was covered in the early part of the season, when, while 



FIG. 62. Rocky Mountain locust; adult and different stages of growth of 

 young. (After Riley.) 



crossing the dry prairies, a good wind often enabled them to cover 

 200 to 300 miles in a day. As they first commenced to alight in 

 their new feeding-grounds their stay was limited to but two or 

 three days, but later in the season it was considerably lengthened, 

 and, after a section was once infested, swarms were seen to be 

 constantly rising and dropping during the middle of the day. 



Life History. Over all the infested area, and while still sweep- 

 ing it bare of crops and vegetation, the females commence to lay 

 their eggs, and continue to deposit them from the middle of August 

 until frost. For this purpose " bare sandy places, especially on 

 high, dry ground, which is tolerably compact and not loose," are 

 preferred. "Meadows and pastures where the grass is closely grazed 

 are much used, while moist or wet ground is generally avoided." 



In such places the female deposits her eggs in masses of about 

 thirty. These are placed about an inch below the surface in 

 a pod-like cavity, which is lined and the eggs are covered by a 



