OUR RIVALS 145 



while proving to him that he is two or three millions 

 off the track either way. 



The woolly aphis is one of the worst in the family, 

 for it floats on the air like a bit of cotton, finding its 

 lodgment in the joints of trees and creating a blister 

 wherever it rests. One of these woolly creatures 

 works just under the ground, creating galls on grapes. 

 Nearly all deposit a honey dew, and this in some cases 

 is utilized, as it is in the case of the psylla, by the 

 bees. 



Among the small friends that aid us in this fight 

 with our small rivals we must count the lady beetles, 

 or as the children call them " carriage bugs." Twice 

 within the last ten years the apple crop has been 

 nearly obliterated in half a dozen states by aphis, and 

 in both cases the evil was mitigated by a parasitic 

 help. 



It was in the summer of 1864, or possibly 1865, 

 that I first saw the potato beetle, then called the. Col- 

 orado beetle, on its first march eastward. I was re- 

 siding in Michigan, and the foul army came by tens 

 of millions, marching straight ahead. When it came 

 to an obstacle it never turned out, but simply climbed 

 and went over, if it could hills and hillocks, fences, 

 and even houses and barns. Going eastward during 

 midsummer, I found them at Niagara Falls just 

 arrived. Every floating chip on Lake Erie carried 

 a stupid, vulgar, stinking beetle. Tens of thousands, 

 of course, were drowned, but enough crossed the 

 lakes and the rivers to make a start. 



