No. 4.] DAWSON — LOCUST INVASION OF 1875. 211 



Missouri. Hatched early in May, especially in the middle 

 western counties. Began leaving early in June, the majority 

 departing about the middle of the month. Main direction of 

 flight, north-westward. 



Iowa. Locusts hatched in a few localities near the south- 

 west boundary of the State. From the 10th of June to the 

 middle of July western counties suffered from swarms passing 

 from south to north. 



Minnesota. Hatched pretty generally throughout western 

 part of State. Some appeared as early as April and were killed 

 by cold and wet. The majority left early in July, and appear 

 to have gone south-westward. 



Dakota. Known to have hatched near the southern boundary 

 of Manitoba. These insects, and those from further north, went 

 southward early in August. During June, and in August, 

 foreign swarms parsed over the State goiug north-westward. 



Montana. Some probably hatched here, and swarms from 

 the east aud south-east appeared during July. 



During the summer of 1875, the conditions described in the 

 Notes for 1874 as occurring in the region west of the 103rd 

 meridian, were reproduced in Manitoba, and over a great area 

 of the Western and South-western States, with results even more 

 disastrous to the crops than those of the winged invasion of the 

 previous year. We do not hear of any access of fresh swarms 

 to Manitoba from the west or north-west, nor is it probable that 

 any such occurred, notwithstanding the fact that in various parts 

 of the province flights are reported to have passed over from 

 north-west to south-east. From the dates and descriptions given, 

 it seems certain, that these were only those from the more remote 

 parts of the province itself, and in many cases the broods hatched 

 in any locality miugled with those coming from a little distance, 

 and departed at the same time. 



The most remarkable and exceptional feature in connec- 

 tion with the appearance of the locusts in 1875, is the extensive 

 invasion of the wooded region east of Manitoba by the swarms 

 produced in the Province. This is the more noticeable when 

 contrasted with the immunity enjoyed by Prince Albert on the 

 Saskatchewan, alluded to in last year's Notes, which is owing to 

 its separation from the general area of the plains by a belt of 

 timber. On writing to Mr. Clarke of Carleton House on the 

 subject, he informs me that this protecting belt of " fir timber " 



