606 REPORT UlNlTED STATES GEOLOGICAL SURVEY. 



to have continned tluriiig the latter part of May and till the 15th of June, while, ao- 

 cordiii<> to Mr. Guuu auil otheis, in cokl, clayey laud and where jxjoIs of water from 

 the nultiiif; of ihe suow lay long, isolated colonies came out at still later dates. Mr. 

 Guun ^^tate8 that grasshoppers were even uoriced to hatch in August and September 

 in 8[)ots which had been covereil with water all summer, a fact showing the very per- 

 sistent vitality of the eggs, and apj>areutly negativing o]»iuiou8 which have been ex- 

 pressed as to their destiuctiou by damp. The most liorrhern locality at vv'hich lucnst.s 

 are rei)nrte(l to have been produced from the egg is at Manitobo. House, Manitoba Lake 

 (latitude 51°). 



'The destruction of crops by the growing insects in all the settled regions was very 

 preat, and iu many districts well-nigh conj])lete. The exodus of these broods began 

 in the early part of July, but appears to have been most geneial during tlje nnddle 

 and latter ]>art of that month and hrst of August. The direction taken on departure 

 was, with very lit tie exce{»tion, southeast or south. It is to be remarked that as there 

 does not seem to have been during this period any remarkable persistency of northwest 

 or northerly winds the insects must have selected those favoring their intended direc- 

 tion of migration, an inst'nct which has very generally been observed elsewhere. 

 Though nuist of the parents, in 1874, came trom the west and northwest, and Manitoba 

 must have represented to those ending their llight there the southeastern limit of their 

 lange, the young insects of lb75 thus took a southeastward direction, just as though 

 starting Ifom their usual breeding-grounds in the far Korth west, and showed no dispo- 

 sition to return to the region whence their parents came. This direction of flight car- 

 ried many of the insects at once into a country of thick woods, swamps, and lakes, 

 and caused the repetition of the phenomenon of the appearance of grasshoppers in 

 great numbers about the Lake of the Woods, a circumstance only once before noted, 

 in the summer of 1857.* This previous occasion, however, differed from that of last 

 year in being an extension of an invasion of Manitoba from the west or northwest and 

 not resulting from insects hatching in that province. 



It is probable that most of the grasshopper swarms of Manitoba thus entering the 

 wooded country were there harmlessly spent, for though some northern swarms reached 

 the State of Minnesota, the invasion api>ear8 to have been comparatively unimportant. 

 Korthern swarms are noted to have passed over Crookstoii (Polk County, Minnesota) 

 and Fort Totten (Dakota), the greatest number appearing at the latter place July ID. 

 The locust swainis described by Mr. Kileyt in the following paragraph, from intoiiua- 

 lion iurnished to the Chicago Tribune, dated July li?, ))robai)l,v also came from Mani- 

 toba: "The iirst Ibieign ho|]peis appeared on ihe Sioux City Road, alighting betweeu 

 Lake Crystal and Saint James on Wednesday last. A few days later they were ob- 

 served at New Ulm flying southeast, and at noon of the same dav struck the line of 

 tiie road at Madelina, Saint James, I'ountain Lake, Wtndom, and Heron Lake, cover- 

 ing the track for about 50 miles of its length." It will be observed on referring to the 

 summary on another page that the insects produced iu Minnesota itself flew southwest 

 in the early part of July. 



I have not been able to trace further the movements of these Manitoba broods, un- 

 less indeed it be supposed that some at least of the swarms which passed over Central 

 Illinois early in Septeujler came fiom that quarter. These, however, Mr. Riley be- 

 lieves not to have been the true migrafry locust, V. sprctiis. 



Foreign swarms from the south crossed the forty-ninth parallel with a wide front 

 stretching from the ninety-eighth to the one hundred and eighth meridian, and are 

 (|uite distinguishable from those produced in the country from the fact that many of 

 them arrived before the latter were mature. These flights constituted the extreme 

 northern part of the army returning northward and northwestward from the States 

 ravaged in the autumn of lb74. They appeared at I'ort Ellice on the loth of June ami 

 at Qii'Apiielle Fort on the 17th of the same mouth, favored much, no doubt, by the 

 steady south and southeast winds, which, according to the meteorological register at 

 Winnipeg, jjievailed on the TJf h of June and for about a week thereafter. After their 

 first ajjpearance, however, their subsecjuent progress seems to have been com])aratively 

 slow and their advancing border Vii-.^ irregular iu outline. They are said to have 

 reached Swan Lake House, the most northern ])oint to which they are known to have 

 attained, about July 10, while Fort Pelly, faither we.-.t, and nearly a degree farther 

 south, was reached July 20, and abotit seven days were occupied in the journey thence 

 to Swan River Barracks, a distance of only 10 miles. If. is more than pr(d)able that 

 the hist southern swarms were followed by others, which minjjled with them, or even, 

 iu parts of Manitoba and the country immediately west of it, with the indigenous 

 brood. From a few localities only in Manitoba, and those in its western portion, is 

 the evidence pretty conclusive as to the arriv:il of foreign swarms from the south. 

 Biirnside, Westbourne, Portage la Prairie, Rockwood, and Pigeon Lake may be men- 

 tioned as alFording instances. 



* Not 18(i7, as erroneously printed in Notes for 1874. 



t From Mr. Charles V. Riley's very interesting Eighth Annual Report on the Noxious 

 Bcneticial and other Insects of the State of Missjuri. 



