No. 4.] DAWSON — LOCUST INVASION OF 1875. 213 



long escape further trouble from these depredators, it is none the 

 less a duty to prepare for a possible repetition of the scenes 

 which have already been witnessed there. In various portions 

 of the United States, the destruction of the young insects has 

 been greatly encouraged by the payment of bounties for that 

 purpose from the public treasuries, but with a plague so wide- 

 spread as that of the locust, the means most likely to lead to 

 permanent amelioration are those capable of general application. 

 The movement in the Western States toward the appointment 

 of a commission by the central government to investigate all 

 the facts connected with the locust trouble, and suggest means 

 for its relief, is in the right direction ; and if such a commission 

 is appointed, it would appear to be of the greatest importance 

 that Canada should take similar action, and at the same time, 

 for its western territory. 



By such general measures as the cultivation and preservation 

 of forest trees, the protection of the prairie grass till the appro- 

 priate time for destroying the young insects in their hatching 

 grounds by fire, and the encouragement of all birds feeding on 

 the young or fledged, imsect, much may be done. The prairie 

 chicken, and the various species of blackbirds, get the credit of 

 devouring great numbers of the young grasshoppers, and if these 

 were protected by more stringent laws, and even a- small increase 

 in safety to the crops resulted, the loss of the one as a game bird 

 and the damage frequently done by the other in the cornfields, 

 would be more than counterbalanced. 



The point of prime importance however in the first instance, 

 is to obtain a complete knowledge of the haunts and habits of 

 the insect under discussion, and as a small contribution towards 

 this end these notes are submitted. 



Mr. G. M. Dodge of Glencoe County, Nebraska, has published 

 a theory relative to the cause or motive of the migrations of the 

 locust, in the Canadian Entomologist for 1875. Mr. Dodge 

 has kindly favoured me with an explanation of this theory. He 

 writes : "I find the insects to be double brooded, flying north in 

 spring to rear a second brood in a region not already devastated. 

 The resulting brood flies south late in autumn, and deposit eggs 

 that lie over winter. This regular movement is complicated by 

 the fact that if the insects of brood first, hatching as far north 

 as this place, should fly north, their progeny might be destroyed 

 by frost; consequently I find that all hatching here or further 



