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dry, permitted an abundance of food in the form of succulent crops* As 
drought increased in 1933 and 1*334 anci crops were ruined, these two species 
decreased almost to the vanishing point. Native grasses in this drought- 
stricken area were better able to withstand dry conditions than cultivated 
crops. M. mexicanus and C_. pellucida withstood the drought because they are 
better adapted to feeding on dry native grass than are either M. bivittatus or 
M. differentials , which are more adapted to cultivated crops and build up in 
abundance in cultivatec areas. These changes greatly affect the method and 
extent of control measures • Melanoplus mexicanus lays its eggs over a much 
wider area than does either Cannula pe llucid a, M. bivittatus , or M. differ- 
entials . This means that larger areas have to be poisoned, involving more 
material and machine scattering to cover the ground. On the other hand, 
Camnula pellucida , Melanoplu s bivittatus , and M. differentials localize their 
eggs along headlands, ditch banks, roadsides, and pastures ana for this reason 
can be more easily controlled. 
Surveys to determine the species and distribution of grasshoppers are 
of great importance. Knowing the economic species and their preferred 
habitats, egg surveys can be concentrated where egrs are most likely to be 
found and, as a result, more accurate estimates can be made in regard to con- 
trol measures that will be needed the following year. 
