5. THE CHERRY. 



AFFECTING THE LEAVES. 



Black wingless lice with a few winged ones, their wings appearing like white 

 parallel lines each side of the hody ; covering the under side of the j oung 

 leaves. 



The Cherrt Plant-louse. Aphis Cerasi, FABKiciua. 



No tree or plant within the sphere of my observation is so con- 

 stantly infested with Aphides as the garden cherry, the Prunus 

 Cerasus of Linnseus, Cerasus vulgaris of modern botanists. Upon 

 other vegetation where these vermin become located they are 

 commonly broken up by their insect enemies after a time and do 

 not again become established upon the same tree. But upon the 

 cherry within a week or two after every individual appears to be 

 destroyed new colonies are discovered to be planted upon one and 

 another of the young leaves. 



This species commences to appear as s^on as the leaves begin 

 to put forth in the spring, these first individuals being hatched 

 from eggs which were deposited the preceding autumn. Ail the 

 individuals which are bred during the spring and summer appear 

 to be females, some of them with wings upon almost every leaf, 

 but most of them without wings. The individuals which are 

 hatched from the eggs resemble the mature wingless females, ex- 

 cept that they are smaller and lighter colored, none of the species 

 of this family passing through those remarkable changes in their 

 form which most of the orders of insects undergo. They bring 

 forth their young alive during the continuance of warm weather. 

 These huddle around their parents upon the under surface of the 

 leaves as closely as they can crowd themselves ; indeed they often 

 are found two deep, a portion of the colony standing upon the 

 backs of the others, requiring only sufficient space between them 

 to insert their beaks into the leaves to suck their juices. The 



