78 
HOP-FLY. 
may often be seen on the hop-leaf ; they are yellow, and 
five or six m a cluster placed on their ends ; these should 
on no account be destroyed, as is too often the case, but on 
the contrary every encouragement should be given to so 
decided a friend to the hop-grower. 
Besides the lady-bird and its grub, there are two other 
terrible enemies to the poor Aphis; one of these is a 
green, ungainly-looking grub, without legs, which lies flat 
on the surface of the leaf, and stretches out its neck, just 
like a leech, till it touches one of them ; directly he feels 
one he seizes it in his teeth, and holds it up, wrigghng in 
the air, till he has sucked all the goodness out of it, and 
left a mere empty skin. This curious creature turns to a 
fly which has a body banded with different colours, and 
which in summer you may often observe under trees and 
about flowers, standing quite still in the air as though 
asleep, yet, if you try to catch him, darting off" like an ar- 
row.* The other has six legs, and very large, strong, 
curved jaws, and is a most ferocious looking fellow, strut- 
ting about with the skins of the blights which he has killed 
on his back. This fierce fellow comes to a very beautiful 
fly, with four wings, all divided into meshes, like a net, 
and two beautiful golden eyes.f All these creatures, 
which thus live on the plant-lice, have a very strong and 
disagreeable smell in the perfect state. J 
* One of the Syrphidce. — E. N. 
f Chrysopa per la. — B. N. 
X I have myself witnessed the operations of a parasite that destroys an im- 
mense number of hop-flies by a most subtle but equally certain process. The 
habits of this minute creature, or one closely allied, have been beautifully de- 
scribed by Mr. Haliday in the ' Entomological Magazine.' In the follow- 
ing passage, cited from 'The Grammar of Entomology,' p. 69, Mr. Hali- 
day's description referring to the parasite of the Aphis of the rose has 
