INSTINCT OF INSECTS. 521 
the wings remained attached, fly away. But a breeze of 
wind acting upon the wings of the fly turned round the 
wasp with its burthen, and impeded its progress. Upon 
this it alighted again on the gravel walk, deliberately saw- 
ed off first one wing and then the other; and having thus 
removed the cause of its embarrassment, flew off with its 
booty*. Could any process of ratiocination be more 
perfect? ‘Something acts upon the wings of this fly 
and impedes my flight. If I wish to reach my nest quickly, 
I must get rid of them—to effect which, the shortest way 
will be to alight again and cut them off.” These reflec- 
tions, or others of similar import, must be supposed to 
have passed through the mind of the wasp, or its actions 
are altogether inexplicable. Instinct might have taught 
it to cut off the wings of all flies, previously to flying 
away with them. But here it first attempted to fly with 
the wings on,—was impeded by a certain cause,—disco- 
vered what this cause was,—and alighted to remove it. 
The chain of evidence seems perfect in proof that no- 
thing but reason could have been its prompter. 
An analogous though less striking fact is mentioned by 
Reaumur on the authority of M. Cossigny, who witness- 
ed it in the Isle of France where the Spheges are accus- 
tomed to bury the bodies of cockroaches along with their 
eggs for provision for their young. He sometimes saw 
one of these Spheges attempt to drag after it into its hole 
a dead cockroach, which was too big to be made to enter 
by allits efforts. After several ineffectual trials the Sphex 
came out, cut off its elytra and some of its legs, and thus 
reduced in compass drew in its prey without diffi- 
culty. 
. one a0 Loe 
a Zoonomia, 1. 183. Reaum. vi. 283. 
