Insects rnjurious to the Apple. 



131 



pliysiolugical cliauyes take placo in t]_Le attacl<bil slioots ami lea\-(is 

 have nevei' been investigated. Why the leaves shouhl, as is Ire- 

 quently noticed, hang on the trees instead nf tailing normally, has 

 not been explained. This is a very marked eharacter in trees that 

 have lie(>n infested with Aphis imiiii , !)(' (iccr. 



Flii. III:!. — Al'l'I.E : 



liV .l;/./.s' f 



With a few exceptions the chief aphides on apple trees have 

 been seen to belong to three species, Jpliis pomi, I>e Geer,"' ^[jilvis 



* This )iaK usually been linown as Ajjliis nuili, l-'abrieius 177."i, but ]:e Geer 

 liad previously described it as Aphis voiiii in 177;!. 



K 2 



