94 INJURIES PRODUCED BY OTHER APHIDES. 



(384.) The rose-tree is commonly infested by an Aphis 

 which feeds upon the tops of the shoots and the adjacent 

 leaves ; and I have been informed by Dr. Fergus that 

 several trees have this year had nearly all their branches 

 destroyed by its ravages. This Aphis seems to have a 

 special aversion to cold water ; a good syringing with 

 which generally compels them all to relax their mis- 

 chievous hold, and a second application commonly washes 

 the whole tribe to perdition. 



(385.) If there is one plant more than another remark- 

 able for its power of resisting destroying agencies, it is, 

 perhaps, the couch-grass ; but I have observed that even 

 this weed has its leaves attacked by a beautifully spotted 

 Aphis, which gradually destroys them and kills the whole 

 plant. 



(386.) The family of Aphides is most numerous, and 

 doubtless all the species act in an equally injurious man- 

 ner. It is not, however, the purport of this work to give 

 a history of the Aphis, and I quote these few instances 

 merely to show that the vastator is not singular in injuring 

 man by its attacks upon various plants. 



