35 



remaining individuals, while at the same time others became literally 



covered with the Locust Mite Trombidium locustarum). In tact, bo 

 extensively were these insects beset with afflictions of one or another 

 kind that but few eggs were deposited. Even where they were, t In- 

 large number of the egg parasites present will likely insure compar- 

 ative immunity from locust attack next year. 



From the northward we have heard but little of tlie pest that at one 

 time last year appeared to be becoming so formidable. In central 

 Idaho and 'portions of Utah and Nevada, where several species did 

 considerable damage to both crops and grasses on tin- range, compara- 

 tively little injury has been reported, while from Colorado, western 

 Kansas, and southwestward, the pest seems to have dwindled to nearly 

 the normal condition for the region. Even in portions of Indiana. 

 Ohio, and other sections of the East, where last year these insects did 

 some injury, the conditions have somewhat improved. 



CAUSES FOR THIS DECREASE IN THEIR NUMBERS. 



It is not at all surprising that these insects have so suddenly become 

 less numerous in the many localities where they were so recently 

 threatening devastation. The large number of parasites and preda- 

 ceous insects which attack them have had an opportunity to increase 

 also. These latter, together with the Entomophthora, which has been 

 unusually abundant and severe during the past few years, have com- 

 bined in reducing the pest. Here in the city of Lincoln and envi- 

 ronments this year the dead bodies of Melanoplus differentialis were 

 to be seen by the thousands clinging to weeds, stems of grasses, and 

 other vegetation, where they were overtaken by death from the et; 

 of the disease. On some single weeds more than a dozen of the hop- 

 pers were frequently to be seen. The dead bodies of other species like 

 the femur-rubrum, bivittatus and atlanis were also occasionally t<» be 

 met with upon the same weeds. These latter were, however, mnch less 

 common. 



One feature observed in connection with the distribution of locusts 

 of this region was the presence in many parts of middle and eastern 

 Nebraska of such species as Dis80steira longipennis and Melanoplus t 

 fns. which must have come from abroad. Here at Lincoln both of these 

 species were of quite common occurrence. On the university campus 

 a female of the former was taken in coitu with a male of l> \ 

 Carolina, Other specimens of the same species were taken at Norfolk. 

 Grand Island, West Point, and Columbus, and even in the vicinity o( 

 Hot Springs. S. Dak. 



Such species as Oamnula peUucida and the glaucous-legged form of M. 

 atlanis^ that have been mentioned on former occasions as gradually 

 moving eastward and southward, were this year met with in rather 

 large numbers in different parts of the Black llill> and even in the 

 northwestern counties of Nebraska. 



