THE AMERICAN BLIGHT. 540 



white cotton soon ajspears in large bunches; branch afttr 

 branch becomes infected ; the tree grows cankery, pines, and 

 dies. How this is effected no one knows, though the j)lague 

 and its doiugs are too evident to escape the notice of the 

 commonest clown. 



' In large orchards it is in vain to hope for a cure, but not so 

 in gardens. Directly you see the least morsel of cotton, make 

 up your minds to a little trouble, and you will get rid of it. In 

 the first place, get a plasterer's whitewashing brush, then get 

 a large pot of double size, make youi- man heat it till it is 

 quite a liquid, then go with him into the garden and see that 

 he paints over every patch of white, though not bigger than a 

 sixpence ; the next morning have the size-pot heated again, 

 and have another hunt, and keep on doing so every morning 

 for a fortnight. Your man will tell you it's no use ; tell him 

 that's your business, not his : your neighbours will laugh at you 

 for your pains ; do it before they are up. I have tried it and 

 known it to be effectual. Spirit of tar has been used with 

 partial effect, so also has resin ; whitewashing has been often 

 tried, and, as it contains some size, is not entirely useless, and 

 some horticulturists think it ornamental ; I do not.' 



Even in the winter time the task of extermination can be 

 carried on. When the weather becomes cold, the Aphides crawl 

 down the trunks of the trees and hide themselves among the 

 roots below the surface of the soil. As they cannot endure tlie 

 cold, the best way of getting rid of them is to expose them to 

 it. So, in the depth of winter, when the thermometer is at its 

 lowest, an inch or two of soil should be scratched up around 

 the trunks of the trees, so as to expose the roots and let the 

 cold air upon the Aphides that are in hiding. The ground 

 should be freshly turned up every day while the frost lasts, 

 and, when the thaw comes, the ground should be well saturated 

 with a solution of ammonia before the earth is replaced. The 

 ammonia-water from the gas-works is amply sufficient for this 

 purpose, is very cheap and easily obtained. 



We now come to the last great group of the Homoptera, 

 namely, the Monomera, or those which have but one joint in 

 the tarsus. These are all included in the genus Coccus, popu- 

 larly known as Scale Insects, on account of the singular form 



