88 BOARD OF AGRICULTURE. 



evident that in Colorado the injury to the potato will always 

 be limited. Five or six miles up Clear Creek Canon, it has 

 injured the potato plants for five or six years, but nowhere 

 above an altitude of about seven thousand feet could I learn 

 that it occurred, and it seems indigenous only to the plains 

 and the canons among the foot-hills. None were to be seen 

 in Utah. 



ITS JOURNEY FROM THE PLAINS EAST OF THE ROCKY MOUN- 

 TAINS TO THE ATLANTIC. 



The history of the successive invasions of the prairies of 

 the Mississipi Valley and of the wooded district of the Mid- 

 dle and North-Eastern States, until only the ocean proved a 

 sufficient barrier to their advances, is a subject of a good 

 deal of interest to the naturalist, whatever may be thought of 

 the dismay with which Eastern farmers have looked upon its 

 arrival. Some years ago, it was confidently announced that 

 the Colorado beetle would not flourish in the damp, cold cli- 

 mate of New England ; that the summers were so wet that it 

 would die while lying as a pupa underground. But at the 

 present time of writing (Sept. 15, 1876), it is doing perhaps 

 as much damage in the North-Eastern States as in the West- 

 ern, and the newspapers report that it has crossed the Atlan- 

 tic and effected a landing in England. If this is so, for the 

 statement needs confirmation, there is no reason why it 

 should not overrun Europe, after successfully withstanding 

 the great differences in climate between the eastern and west- 

 ern regions of the United States. This insect, so indifferent 

 to ordinary climatic differences, may be compared to a weed 

 which, introduced in a new country, overruns and displaces 

 the native vegetation. Like weeds, the Colorado potato-bee- 

 tle, with a number of other widely destructive insects, may 

 be regarded as prepotent animals. 



Fortunately for the historian of the movements of this 

 insect, the late Mr. B. D. Walsh, at an early date after it 

 began to spread eastward from the plains of Colorado, pub- 

 lished in the "Practical Entomologist," Vol. 1, No. 1, Octo- 

 ber, 1865, an account of its travels. In 1859, it had, in its 

 journey eastward, reached a point one hundred miles west of 

 Omaha, Nebraska. It appeared in Kansas and Iowa in 1861. 



