192 Editor's Letter-Box. • 



Injurious to Vegetation, Packard's Guide to the Study of Insects, and the 

 American Entomologist, all of which we would advise you to consult for further 

 information whenever you have opportunity, as its history is very curious and 

 interesting. There is also an interesting article on the bark louse, in vol. ii. p. 

 85, of this Journal. 



In the spring, the eggs are readily to be seen by raising the little muscle-shaped 

 scales beneath which they are concealed. These eggs are of a white color, and 

 in shape nearly like those of snakes. Every shell contains from th'rty to forty 

 of them, embedded in a small quantity of whitish friable down. They begin to 

 hatch about the 25th of May, and finish about the loth of June, in New England. 

 The young, in their first appearance, are nearly white, very minute, and nearly 

 oval in form. In about ten days they become stationary, and early in June throw 

 out a quantity of bluish-white down, soon after which their transformations are 

 completed, and the females become fertile, and deposit their eggs. These, it 

 seems, are hatched in the course of the summer, and the young ones come to 

 their growth, and provide for a new brood before the ensuing winter. 



This insect multiplies with astonishing rapidity. The best time to attack them 

 is when just hatched, and before they become stationary, that is, about the first 

 of June, by syringing with strong tobacco water,, scraping and soaping the bark, 

 two parts of soft soap, and eight of water being mixed with lime enough to 

 bring it to the consistence of thick whitewash. Or a solution of a pound of pot- 

 ash, or a quart of common salt in a pail of water, may be used. It has also been 

 recommended to boil pitch or linseed oil with, the tobacco or tallow, to keep it 

 from washing off, and apply it early, so as to prevent the eggs being deposited. 

 About two weeks after syringing, as first directed, the terminal twigs may be cut 

 off and burnt, to destroy any that have escaped the syringing process, as they 

 prefer to fix themselves around the ends and knots of such terminal twigs. 

 They never attack rough bark. The lady-birds, which devour this as well as 

 the native white species, should also be encouraged. This lady-bird is a little 

 roundish beetle, about a quarter of an inch in length, black, with a red spot in 

 the fore part of each of its wing-covers, and pre)'s upon the newly-hatched bark 

 lice in a most savage manner. Dr. Shimer has also discovered a mite, which 

 sucks the eggs in autumn. 



Idem. — We thought our readers would get some new ideas from the chapter 

 on grafting, which we published a year ago ; and we are glad to know that you 

 were pleased with it. We will try, when the season for budding approaches, 

 what we can do on that subject. 



T. R., Worcester, Mass. — The best way to prevent moss from growing on 

 pear trees, is to keep the trees thrifty. Not only insects, but all parasitic plants, 

 like moss, are most likely to attack an unthrifty tree. The bark of the most 

 vigorous tree will in time become rough, and then the moss is apt to find a lodg- 

 ment ; and though a little will do no harm, if you dislike the looks, you can 

 scrape it off w'ithout injuring the tree. Do not, however, scrape any more than 

 is nt* isary to remove the moss. 



