Insects Injurious to Agriculture. 115 



the larva, and thus remains, the old larva skin continuing to 

 cover the pupa on each side and beneath. The insect remains 

 dormant in its pupa state about a fortnight, when its hard 

 exterior shell cracks open, and from it crawls a small shining 

 beetle nearly the shape of a half pea, though often much 

 smaller than this." 



The Agents Within Ouk Control for Destroying 

 Plant Lice. — The smoke of tobacco, when it is possible to 

 confine it for a time, is undoubtedly one of the most efficient 

 remedies for extinguishing these pests. In green houses, 

 graperies, consei-vatories, etc., the smoke is always potent. 

 Small out-door plants can be covered with boxes, barrels, or 

 even umbrellas, or anything that will form a temporary cover, 

 will answer, and insure the destruction of the aphides with 

 tobacco smoke. But on large trees, and vines, smoking is not 

 practicable. The next best thing is a thorough drenching 

 with strong tobacco water ; say one-fourth of a pound of 

 tobacco to one gallon of boiling water. Soap suds has been 

 used with good results. A strong decoction of quassia wood 

 has also been attended with some benefit. But of all reme- 

 dies for out-door trees and \dnes, I prefer collecting, with a 

 net, by sweeping bushes and coarse weeds, the several larv» 

 described in this article — cqohis-lions and aphis-ioolves. 



Several years ago a fine balsam fir, fifteen feet in height, 

 standing in my grounds, became overrun with a species of 

 woolly aphis, which deformed the leaves, and there was dan- 

 ger of the tree being destroyed by them. With a net I col- 

 lected a brave lot of the larvae of lady birds, and placed them 

 on the lousy tree ; at the same time I noticed several packets 

 of lace-wing eggs. The combined labors of these soon des- 

 troyed every single louse. The tree, now sixty feet in height, 

 has never, to my knowledge, had an aphis on it since. 



Last year my out-door gTapes became badly infested with 

 lice ; I secured many aphis-wolves and aphis-lions, which I 



