OBSERVATIONS ON INSECTS AND VERMES. 293 



OESTRUS CURVICAUDA. 



This insect lays its nits or eggs on horses' legs, flanks, &c., each on a 

 single hair. The maggots, when hatched, do not enter the horses' 

 skins, but fall to the ground. It seems to abound most in moist, 

 moorish places, though sometimes seen in the uplands. WHITE. 



NOSE-FLY. 



About the beginning of July, a species'of fly (musca) obtains, which 

 proves very tormenting to horses, trying still to enter their nostrils 

 and ears, and actually laying their eggs in the latter of those organs, or 

 perhaps in both. When these abound, horses in woodland districts 

 become 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. WHITE. 



Is not this insect the Oestrus nasalis of Linnaeus, so well described 

 by Mr. Clark in the third volume of the " Linnsean Transactions," 

 under the name of Oestrus veterinus ? MARKWICK. 



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 resistance, the 

 ichneumon applied her tail to him, and stung him with great 

 vehemence, so that he soon became dead and motionless. The ich- 

 neumon 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 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 butterflies. WHITE. 



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 chrysales 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 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 their larva ; but none more remarkable 

 than that of the ichneumon tipulce, which pierces the tender bodies and 

 deposits its eggs in the larva of the Tipula tritici, an insect which, 



