290 OBSERVATIONS ON INSECTS AND VERMES. 
ensue. In the heat of the day, men are often obliged to desist 
from ploughing. Saddle-horses are also very troublesome at 
such seasons. Country people call this insect the nose fly.* 
ICHNEUMON FLY. 
I SAW lately a small ichneumon fly attack a spider much larger 
than itself on a grass walk. When the spider made any resist- 
ance, the ichneumon applied her tail to him, and stung him with 
great vehemence, so that he soon became dead and motionless. 
The ichneumon then running backward drew her prey very 
nimbly over the walk into the standing grass. This spider would 
be deposited in some hole where the ichneumon would lay some 
eggs ; and as soon as the eggs were hatched, the carcase would 
aflford ready food for the maggots. 
Perhaps some eggs might be injected into the body of the 
spider, in the act of stinging. Some ichneumons deposit their 
eggs in the aurelia of moths and butterflies.f 
BOMBYLIUS MEDIUS. 
The homhylius medius is much about in March and the begin- 
ning of April, and soon seems to retire. It *;s an hairy insect, 
like an humble-bee, but with only two wings, and a long straight 
beak, with which it sucks the early flowers. The female seems 
to lay its eggs as it poises on its wings, by striking its tail on 
the ground, and against the grass that stands in its way, in a 
quick manner, for several times together.^ 
• Is not this insect the oestrus nasalis of Linnseus, so well described by Mr. Clark in the thirc 
volume of theLinnsean Transactions, under the name of oestrus veterinus P—Mavlkv/ics.. 
t In my Naturalist's Calendar for 1795, July 21st, I find the following note: — 
It is not uncommon for some of the species of ichneumon flies to deposit their eggs in the 
chrysalis of a butterfly :* some time ago 1 put two of the chrysalis of a butterfly into a box anc 
covered it with gauze, to discover what species of butterfly they would produce ; but, instead of? 
butterfly, one of them produced a number of small ichneumon flies. 
There are many instances of the great service these little insects are to mankind in reducing 
the number of noxious insects, by depositing their eggs in the soft bodies of thei larva; bu 
none more remarkable than that of the ichneumon tipula, which pierces the tender body and 
deposits its eggs in the larva of the Hpiila tritici, an insect which, when it abounds greatly, ij 
very prejudicial to the grains of wheat. This operation 1 have frequently seen it perform with 
wonder and delight.* — Markwick. 
* Some minute species deposit their ova in the eg^s of other insects. — Ed. 
t I have often seen this insect fly with great velocity, stop on a sudden, hang in the air in a 
stationary position for some time, and then fly ofl^ again ; but do not recollect having ever seen i' 
strike its tail against the ground, or any other substance.— Markwick. 
