350 OBSERVATIONS ON 



very impatient at their work, continually tossing their heads, 

 and rubbing their noses on each other, regardless of the 

 driver, so that accidents often 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. 1 



ICHNEUMON FLY. 



1 SAW lately a small ichneumon fly attack a spider much 

 larger than itself on a grass walk. When the spider made 

 any resistance, the ichneumon applied her tail to him, 

 and stung him with great vehemence, so that he soon 

 became dead and motionless. The ichneumon then run- 

 ning backward, drew her prey very nimbly over the 

 walk into the standing grass. This spider would be de- 

 posited in some hole where the ichneumon would lay some 

 eggs ; and as soon as the eggs were hatched, the carcass 

 would afford 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 buttei flies. 2 



1 Is not this insect the CEstrus nasalis of Linnasus, so well described 

 by Mr. Clark in the third volume of the Linnean Transactions, under 

 the name of CEstrm veterinus. MARKWICK. 



2 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 I put 

 two of the chrysalis of a butterfly into a box, and covered it with 

 gauze, to discover what species of butterfly they would produce; but 

 instead of a butterfly, one of them produced a number of small ich- 

 neumon 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 their larvce ; but none more remarkable 

 than that of the Ichneumon tipulce, which pierces the tender body and 

 deposits its eggs in the larva of the Tipula tritici, \_Cecidomyia tritici, 

 Kirby ED.] an insect which, when it abounds greatly, is very pre- 

 judicial to the grains of wheat. This operation I have frequently seen 

 it perform with wonder and delight. MAKKWICK. 



