INSECTS. 317 



their wonderful increase, and sometimes will utterly rout 

 the Aphides in a single week.* 



The remedies advised for the apple tree Aphides, are 

 equally applicable to those of the cherry, and their natural 

 enemies are the same and equally efficacious ; but Aphides 

 have internal foes likewise, that may be named here. The 

 Ichneumon-flies are parasitic, their larvae feed upon the 

 substance of the Aphides. The genus Aphidius is parti- 

 cularly provided to furnish parasites to these insects, in 

 which they deposit a single egg, selecting a louse of the 

 proper size to sustain their progeny : the egg hatches to 

 a larva, which exhausts the Aphis by the time it has at- 

 tained its growth, when the poor creature fastens itself 

 securely to the leaf, and dies, leaving its carcase a secure 

 resting place for the pupa of the Ichneumon. These para- 

 sitic insects, which feed internally upon the Aphides, are 

 as effective in their destruction as the Aphis-lions, or any 

 other class of their enemies.* * 



Aphis persicaBj or the Peach Tree-louse, punctures the 

 leaves of this plant, and Dr. Fitch f thinks, is the common 

 though not the only cause of the curl in the peach tree 

 leaves. Our intelligent orchardists have found these in- 

 sects occasionally in the curled leaves of the peach, but do 

 not agree with this distinguished entomologist, in consid- 

 ering them a cause of that malady. 



Aphis Vitis I, or the Vine Aphis, is often quite trouble- 

 some on vigorous young shoots of the grape vine, both 

 wild and cultivated, particularly the former. These in- 



* Rept. cit. p. 125. 



* * Rept. cit. p. 134. 



t Trans. N. Y. Ag'l Soc., 1856, p. 359. 



