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possible with the insect race, that we may know 
the difference betwixt those that befriend us and 
those that do not. 
I remember in the year 1823, in the neigh- 
bourhood of Pontefract, being much struck with 
the singular appearance of an orchard of Apple 
trees being stripped of their exterior bark, and on 
inquiring why they were thus treated, the principal 
reply was, that it was of great service in destroy- 
ing insects, for, says the person, “ When taking 
of the bark, I found great quantities of them lodg- 
ed under it,” from which observation I found that 
he was injuring his particular friend, the Lady- 
bird, and not his enemy, as he supposed. 
Another destroyer of the Aphides is the larvae 
of the Fly (I believe Musca Pyrastri) which is 
frequently in hot days seen steadily hovering above 
a particular spot, as though it was suspended in 
the air, alternately darting horizontally and in 
other directions in the air. It appears that the 
fly deposits her eggs among the Aphis, to which 
she is no doubt first attracted to feed on the 
saccarine fluid they eject. They do not of them- 
selves destroy the Aphides, but the larvae they 
produce commence their ravenous pursuits very 
soon after coming into existence. The eruca or 
lai'vae is uncommonly soft, and faintly variegated ; 
the head and hinder pai-t are acute; the whole 
form is much that of a leech in miniature. 
It is also said that ants are great enemies to 
the Aphides. I cannot be positive respecting this. 
