26 LETTERS ON ENTOMOLOGY. 
is in vain the victim seeks to avoid the fatal 
wound ; the merciless fly does not leave it till 
she has deposited a sufficient number of eggs, 
and the poor caterpillar is forced to carry about 
her mortal enemies, which feed on her inside but 
never touch her vitals, though they are frequently 
in great numbers. 
Of thirty cabbage caterpillars which Reaumur 
put into a glass to feed, twenty- five were fatally 
pierced by an ichneumon ; from which we may 
judge of the great destruction of these injurious 
insects, which if suffered to increase, would 
become as great a plague as the locusts, and 
indeed have frequently been known to do serious 
damage. 
I cannot here enumerate all the species which 
prey upon each other, but I will mention some 
of the principal among those which devour the 
perfect insect. Ants, wasps, and hornets, are, 
among others, distinguished in this sanguinary 
or rather warlike respect; an ant will carry 
away a bee many times bigger than itself, and 
has even, with the help of its comrades, been 
seen to drag a young snake as thick as a goose- 
quill. A young lady told me she once saw a 
battle between a wasp and a bee, in which the 
former bit off all her enemy's six legs. Where 
