Chronological History 37 



season. The damage, however, was not general, and good 

 crops were harvested in most of the country invaded the 

 year before. But later in the season fresh swarms came 

 from the Rocky Mountain region, and fell upon the fertile 

 plains of the Mississippi Valley. Thus there were two 

 fresh invasions, the one following the other, in the years 



1866 and 1867 ; an occurrence which is quite exceptional, 

 and to which the immens') damage done during the latter 

 year is, in great part, attributable. Mr. Walsh (loc. cit.) 

 has given us, at great pains, a pretty full record of the 

 doings of locusts in 1867, and from said record he makes 

 it quite clear that the invasion of 1866 was followed in 



1867 by a fresh, though less extensive one, direct from 

 the Rocky Mountain region. I may add that a number of 

 scraps and records of the insect's doings during those two 

 years, other than those he has brought together, bear out 

 his deductions. The locusts also fell upon Utah in 

 immense swarms in 1867. 



During the subsequent years of 1868 and 1869 we hear 

 more or less of the remnants of these two vast swarms 

 from the mountain region, and of their injury in the Mis- 

 sissippi Valley; but their numbers are always diminishing 

 and their enemies increasing, so that during the latter year 

 not a healthy individual was to be found, and in 1870 the 

 race had nearly vanished from the invaded country — at 

 least from its eastern portions. In 1868, they were par- 

 ticularly disastrous in Utah and the Red River Settlement 

 of British America. 



In 1869 there were still some remnants left of the 1867 

 invasion. From Leavenworth, Kansas, I received some, 

 sent in a tin box, and in reaching me there was but one 

 left, which, having eaten the others, was master of the 

 situation. They hatched out in countless numbers from 

 the 20th to 24th of March, in Holt county, Mo., and 



