DESTINATION OF EASTERN SWARMS. 177 



August 6. In refereuce to the last, he remarks that " the lower curreut 

 was moving a little east of north in coosiderable numbers. An equally 

 heavy column was moving toward the south above the one last men- 

 tioned. 



Oar correspondent at Menannah, Meeker County, Minnesota, observed 

 the same thing on the 3d of July. 



The correspondent at Tenhassen, Martin County, Minnesota, states 

 that on the 5th of July an upper swarm flew west while a lower swarm 

 was moving northwest very thick. A similar case occurred at Delafield, 

 Jackson County, Minnesota, July 6. Eev. S. E. Riggs, missionary at 

 Sisseton agency Dakota, states in a letter to Professor Whitman that 

 on the 6th of July he '* observed that while the surface wind blew pretty 

 strong from the south the fliers were moving toicard the southwest, 

 probably on a counter current higher up." 



TO WHAT EXTENT DID THE BETURNING SWARMS IN 1877 PASS ON- 

 WARD TO THEIR NATIVE HATCHINa GROUNDS^ 



The direction taken by these swarms in May and June, as heretofore 

 stated, was northward, generally northwest or a little west of north. If 

 the object of these flights was to reach the hatching grounds from 

 which their progenitors came, then to accomplish it they must pass into 

 the Northwest Territory of British America or the northwest part of 

 Dakota and eastern part of Montana, unless the country about the 

 Black Hills of Dakota is found to be a permanent breeding ground, in 

 the sense heretofore explained, which is rendered probable from facts 

 ascertained during the past year. It is impossible to answer this ques- 

 tion definitely at present, as but few reports have been received up to 

 this time from British America. Still we may arrive at a tolerably 

 correct conclusion from our own observations and the data we have 

 obtained. Mr. Eiley while in Manitoba, during the latter part of 

 August, ascertained that no swarms had visited that province in 1877 

 up to that time. From Captain Stewart Moore, of Prince Albert Mis- 

 sion, who had just come from Edmonton, Northwestern Territory, he as- 

 certained that locusts flew from the south early in July as far north- 

 west as the vicinity of Battle Eiver. Mr. A. Fuller also reported them 

 some distance north of Battleford. Eeports were also received showing 

 that swarms were observed passing northward in the vicinity of Cypress 

 Hills. While these reports show that some did succeed in reaching 

 their permanent breeding grounds, yet the indications furnished by the 

 reports themselves and the absence of other reports leave a very strong 

 impression that this return was insignificant compared with that of 

 1875, and this impression is deepened into conviction from what we 

 know in reference to their movements south of the international 

 boundary. 



Those that left Western Texas about the 1st of May were probably 

 the same that terminated their flight at Black Hills in the latter part of 

 the same month, and there deposited eggs. This supposition is ren- 

 12 a 



