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from the dry rot; but, beyond the selection of the seed, 

 no preventive means have yet been successfully applied. 

 The wet rot is caused by certain species of bacteria, 

 chiefly Bacillus amylobacter. 



Insect Attacks. 



Insect attacks on English-grown potatoes are most 

 commonly directed to the destruction of the plant 

 below ground. The Colorado beetle, Doryphora 

 decemlmeata, which caused a great scare in England 

 a few years ago, did not find it a suitable home, 

 though it still does great injury to American crops 

 by eating the leaves. The insect is kept in check by 

 means of a spraying of Paris green in solution, which 

 proves very effective, and is commonly used in 

 America and Canada. 



The Potato Frog fly (Eupterix solani) is commonly 

 found in England, but not in sufficient quantities to do 

 serious injury. This insect attacks the leaves, sucking 

 out the sap. It is very small, the wings, when 

 extended, being less than a quarter of an inch in 

 breadth, while the length of the insect is only about 

 one-twelfth of an inch. The attacks have proved so 

 unimportant that no steps have been taken to check it. 



The caterpillar of the Death's-head moth feeds on 

 the leaves of the potato, but fortunately it is not 

 sufficiently plentiful to do serious injury, or from its 

 great size it would rapidly devastate crops. This 

 handsome caterpillar, four or five inches in length, is 

 of a greenish yellow, speckled with black on the back, 



