Appendix Entomology of the Rose. 373 



The last of the aphidivorous insects are the larva of the DIPTEROUS genus, Syrphus (family 

 Syrphince), all of which feed on Aphides, and where these abound perhaps the Aphis has no 

 more voracious or implacable foe. These larvae are blind, and are furnished with a three- 

 pronged mandible, after the fashion of a trident, and groping about amongst their victims, they 

 seize them with this powerful instrument, and elevating them in the air suck their juices like 

 the larva last named, leaving the skins on the leaves. 



We might add to these friends of the Rose, in a lesser degree, dragon-flies, sand-wasps, and 

 a number of others which in the various stages of their existence prey upon other insects, thus 

 limiting their powers of increase, and rendering them incapable of overstepping the bounds 

 assigned them in the economy of nature. 



