degree, but. still occurring,) in the Mississippi and Red River 



valleys during the last thirteen years. And these nine attacks 

 stiind against some seven or eight recorded appearances of destruc- 

 tive locusts in the same territory during the 46 years preceding, 

 from 1818 to 1864. Agaiit We have on the one hand the sudden 

 appearance of the immense swarms which are said to have over- 

 run a vast extent on both sides of the Rocky Mountains in 1855, 

 the gradual disappearance of their progeny in the course of the 

 next three years, apparently without furnishing material for 

 future invasions, and their continued absence for the next six 

 years. On the other hand we have, since 1864, a series of attacks 

 occurring at intervals of one, two, or at most three years, and 

 apparently of late an annual vibration between the country lying 

 along the mountains and the lower cultivated regions, each in its 

 turn becoming a breeding-ground. The causes of the increase 

 and continuance of the evil of late years lie outside the range of 

 common observation. That they do not result entirely from an 

 increase of acreage under cultivation, is to be inferred from the 

 locust history of other countries, and from the facts that while 

 Central America has suffered from the same evil at least as far 

 back as 1514 (Bancroft's Native Races of the Pacific Coast, vol. 

 v., page 601,) and Mexico and California at least as lately as 1855, 

 the exemption of these countries since the latter date has been as 

 noticeable as the repeated devastation of our own vicinity. As 

 for any analogy to be derived from the locust history of European 

 countries the books are not at hand in this state to furnish the 

 exact chronology of the evil ; but from such a source as I have at 

 hand, the record of Germany for the last four centuries shows 

 intervals of exemption from injury for eight, twelve, sixteen, 

 forty (1T63— 1803,) or even fifty (1636—1686) years, and again no 

 less than fourteen years of injury between 1727 and 1755, and 

 among these series of three, four, or even five successive years of 

 damage, as in the five years from 1727 to 1731, and again from 

 1746 to 1750.* 



* Those dates are taken from a work entitled, Die Kleiuen Feinde der 

 Landwirthschaft, by Prof. H. Nordlinger, Stuttgart], 1855, furnished by the 

 kindness of Gustav Kyllander, Esq., of Severance, Sibley county. For a 

 systematic and connected view of the locust evil in general see a paper 

 contained in the Report (for 1876) of the Hon. Commissioner of Statistics 

 of Minnesota, Dr. J. B. Phillips. Notice is particularly called to a chrono- 

 logical table published therein. It will be seen that there is no state or 

 territory west of the Mississippi that is not in the " grasshopper regions,' 

 and no year since 1863 that has not been a locust year. The year 1871 should 

 be included in the table, for reasons stated in this report. 



