PACKAKD.j THE MIGRATIONS OF THE LOCUST. G43 



the locusts is maturing, the ejjgs ripening, and the uneasiness of the 

 locnsts during- the course of their travels may be unconsciously stimu- 

 lated by the sexual instincts and the desire to discover suitable places 

 lor egg laying, a long and tedious operation. 



It has been sufficiently shown that a swarm of locusts observed by Pro- 

 fessor liobinson near the entrance to Boulder CcIudii, Colorado, traveled 

 a distance of about six hundred miles to Eastern Kansas and Missouri. 

 Though the swarm was first observed at some distance north of Denver, 

 Colo., it was then on its way from the north, and may have come from 

 some part of Wyoming two or three hundred miles northwestward or 

 northward. Though the winds may vary and counter-currents exist, 

 and storm-gusts from due north, such as often sweep over the plains, 

 and local southerly breezes may retard their flight, tlie course is either 

 eastward or southeasterly. We know enough of the winds in the West- 

 ern States and Territories to lay down the the law that the general direc- 

 tion of the winds in July and August, along the eastern slope of the 

 liocky Mountains and on the plains, is from the west and northwest, 

 and accords with the eastward course of the locust swarms. The rela- 

 tions between the average direction of the winds and the migrations of 

 tlie locust have, however, never been sufficieutly studied, either, so tar 

 as sve are aware, in Europe or in this country. And yet, if we would 

 intelligently study the causes of the excessive increase and migrations 

 of the locust, we must examine the meteorological features of the country, 

 ascertain the periods of drought and undue rain-fall, the average direc- 

 tion of the wind for the different months, in order to learn how far they 

 co-respond with the phenomena of insect-life. That there are meteor- 

 ological cycles, dry and hot seasons recurring at irregular intervals, 

 while the general average may remain nearly the same century after 

 century, is supported, though it may be vaguely, by observed meteor- 

 ological facts. 



The question then arises. Can meteorologists predict the coming of sea- 

 sons of undue heat and dr.night, and consequently can we predict insect- 

 yearsf That is, the migrations of locusts and the undue increase of the 

 chinch-bug and armg and cotton tvorni f 1 believe that we shall, afrer the 

 lapse of years, be able to foretell with a good degree of certainty locust 

 invasions, and be able to provide against the losses thus incurrred. 



On the frontier of the Western States, in Colorado, or in the Territo- 

 ries of Wyoming, Montana, and Utah, where the losses from the rav- 

 ages of the locust cannot easily be made up by iniportations from con- 

 tiguous Territories, it seems the most practicable mode to provide in 

 years of identy against years of want. We should imitate on a grand 

 scale the usage of tlie ancient Egyptians under Pharaoh, who laid up in 

 times of unusual harvest stores ol grain for times of famine. It is said 

 that this has been done on a small scale by the Mormons. If this were 

 done in the far West, in seasons immediately preceding insect-years, 

 which had been predicted by entomologists in conjunction with the 

 meteorologists, we should be saved the distress, destitution, and even 

 loss of liie from starvation, which have resulted from ignorance of the 

 laws regulating the ai)pearauce of destructive insects, especially the 

 western locust. 



The return migration. — By simultaneous observations for a number of 

 years over the region liable to be visited by migratory hordes of locusts, 

 added to the knowledge we already possess, it will not only be possible 

 to predict the course of certain swarms from their breeding-places, and 

 their probable destination, so that when a swarm starts trom Montana 

 or Wyoming, its arrival in Colorado a week or a fortnight later may 



