Chronological History. 



51 



A detailed record of this invasion published in the 9th 

 Mo. Entomological Report, makes it manifest that the 

 locusts that hatched and did more or less damage in 

 Minnesota early in the year, endeavored to get away to the 

 northwest as soon as they acquired wings. They were 

 subsequently repulsed and borne back again by the winds 

 to their hatching places ; thence south and southwest into 

 Iowa and Nebraska. As they rise and fly from day to day 

 they concentrate and condense, since in passing over a 

 given area during the hotter parts of the day new acces- 

 sions are constantly being made to the flying hosts which, 

 with serried ranks, descend in the afternoon. Thus, in 

 returning, the swarms were thicker and more destructive in 

 places than they were in leaving. Yet the column which 

 thus came back to Minnesota and passed to the south and 

 southwest was more straggling than in 1874, and by the 

 middle of the month it had spent its force and left eggs 

 throughout most of the country traversed. Had the 

 invasion consisted of these alone, the damage would have 

 been but slight, and the insects would hardly have reached 

 into Kansas. Their eggs, laid in August, were far more 

 liable to injury and to premature hatching than those laid 

 later. But fresh swarms that hatched in Dakota, and 

 farther northwest, followed on the heels of the Minnesota 

 swarms, passing over much of the same country to the 

 east and southward into Colorado, and eventually over- 

 running the larger part of Nebraska and Kansas, the 

 western half of Iowa and some of the western counties 

 in Missouri, and reaching into Indian Territory, Texas, and 

 parts of Arkansas. 



The extent of the region invaded will appear by referring 

 to the map (Plate III). Coming generally later than in 

 1874, they did less damage, and the farmers were in so 

 much better condition to withstand injury, that it was- 



