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characterized by the incoming of fresh and still active swarms 

 lute in August, and these have been carried by winds blowing 

 freshly from the west, as far east as Mower county, longitude 16° 

 vest. It may be proved in future that the eastern limit of in- 

 vasion is determined solely by the extent to which winds prevail 

 from the west, together with the length of the season during 

 which the locust retains its full activity and strength. The con- 

 nection between the movements of the locust and the prevailing 

 direction of the winds, seems likely to receive more attention than 

 has hitherto been paid to it. While the timbered country of the 

 northeastern part of the State has been but little infested, to any 

 great distance east of the Mississippi, it may be said that that 

 portion of the state does not lie in the direct line of invasions. 

 There is nothing to show that swarms purposely turn aside from 

 the heavily timbered regions and go elsewhere, although in par- 

 tially timbered sections they alight mostly in the open farms. 

 But, having once entered the timber, their progress is soon ended, 

 and no more fortunate destination could be selected for our depart- 

 ing swarms than Northeastern Minnesota. Locusts have been 

 quite numerous about Brainerd throughout the summer, since 

 ■early in July, and their numbers were perceptibly increased on the 

 sixth of August, apparently brought in by a strong Avind from the 

 southwest ; but these evidently found their progress impeded by 

 the timber, for they did not extend to any distance east of Brainerd, 

 along the Northern Pacific Railroad, nor did the}' lay eggs to any 

 extent about Brainerd. 



The connection between flying movements and the direction of 

 the winds may be shown by the following diary kept by Lieut. It. 

 B. Plotts, of Elk toAvnship, Nobles county: 



July 5. — "Light wind; flrst flight came from the northeast, aud com- 

 menced to settle down about 10 a. m. ; attacked gardens first of all. They 

 remained here till Sunday, the 9th, wheu in a brisk breeze from north-north- 

 west, a light rain the night before, th»y flew from early in the morning till 

 after sundown, and lit heavily south of me. 



July 10. — " Wind southeast; flew heavily to the west, the highest appear- 

 ing to sheer oft' southwest. Got a heavy light from those east of me. 



July 13.— " Late in the afternoon wind suddenly veered to northeast, and 

 they started immediately. Nearly all lefc me. 



July 15. — " Wind north, veering to the east. Not a very heavy flight to 

 the west. 



July 16. — " Wind south-southeast. Still going west. 



July 17.—" Wind east, trending north, showery. Before the showers 

 commenced, could be seen goiug west. That ended the first raid. No more 

 /lying over till 

 4 



