70 INSKCTS INJUIITOUS TO STAPLE CROPS. 



characterized by two yellowish stripes extending from the 

 eyes along the sides of the head and thorax to the extremi- 

 ties of the wing-covers, and is probably the species most 

 commonly observed by the farmer. 



The Differential Locust. 



An nnusnally severe outbreak of the Differential Locust 

 occurred in Mississippi and Louisiana in 1899 and 1900 

 and was quite fully investigated by Prof. H. A. Morgan^ 

 and interestingly reported upon by him.* It seems that 

 outbreaks of this grasshopper invariably occur immediately 

 after an overflow of the Mississippi or crevasses through 

 the levees, which inundate the surrounding country, caus- 

 ing a rank growth of vegetation and rendering the land 

 unfit for cultivation for a season or two, during which time 

 the grasshoppers have every opportunity for rapidly 

 increasing in abnormal numbers. *^ Should heavy rains 

 prevail during May and June of the season immediately 

 following the crevasse, nothing is heard of the ravages of 

 grasshoppers; but should dry summers follow, the condi- 

 tions for grasshopper propagation and development are 

 much more favorable and complaints are common." 

 " The habits of young grasshoppers to seek the soil-crevices 

 during rain results in the burial of millions beyond the 

 hope of resurrection. This, with the development and 

 propagation of fungous diseases among the nj^mphs, are 

 the most potent natural agencies which destroy grass- 

 hoppers during wet summers." f In 1899 thousands of 

 acres of cotton, corn, and other crops were totally destroyed 



*See Bulletin 30, n. s., Div. Ent., U. S. Dept. Agr., pp. 7-33. 

 \ Morgan, 1. c, p. 33. 



