SB ^^^ C^JRTis's Obfervations on Aphides. 



fycamoie, which is much iTiCre agile than many of this race, en- 

 deavour to avoid the Ichneumon with great addreis. 



There is, perhaps, no genus of infects which in their larva or 

 man-got (late feed on fuch a variety of food as the Mufca^ or Fly. 

 There is fcarcely a part of nature, either animate or inanimate, 

 in which they are not to be m.et with. Onedivifion of them, called 

 by Linnaeus Mufo-e aphidivone, feeds entirely on Aphides, Of the 

 different fpecies of aphidivorous flies, which are numerous, having 

 moftly bodies variegated with tranfverfe ftripes, their females may 

 be fcen hovering over plants infcfted with Aphides^ among which 

 they dcpofit their eggs, on the furface of the leaf. The larva^ or 

 maggot, produced from fuch eggs feeds, as foon as hatched, on the 

 younger kinds of Aphis\ and, as it increafes in fize, attacks and de- 

 vours thofe which are larger. Thefe larva are ufually of a pale 

 colour, adhere clofely to the leaf, along which they flowly glide, 

 and are formed very tapering towards the head. When fully 

 grown, they change to 2. pupa ^ or chryfalis^ attached to the leaf, from 

 whence iffues the fly. The larvcc of thefe flies contribute their 

 full fhare to diminiili the defpoilers of Flora. To thefe three kinds 

 of infe6ls, which are the chief agents in the hands of Nature for 

 keeping the ^/>/j?V<?j within their proper limits, we may add a few 

 others which a6l a fubordinate part in this neceffary bufmefs of 

 deftru6lion. 



The larva of the Hemerobius feeds on them in the fame manner 

 as that of the Mufca aphidivora^ and depofits its eggs alfo on the 

 leaves of fuch plants as are befet with Aphides, The eggs of thhs 

 Hernerobius ftand on long filaments, which are attached by a bafe to 

 the leaf, and have more the appearance of the filaments of flowers 

 with their mtljent than the eo;gs of an animal. 1 he number of 



thefe 



