6172 



Insects, 



Clarif, no doubt a better appellation, as neither does its bot inhabit the 

 nostrils of any animal, nor is it the well-known "nose fly" of our 

 English rustics, which is the (E. hoemorrhoidalis. Of this latter. 

 White of Selborne remarks that, "About the beginning of July a 

 species of fly obtains, which proves very toimenting to horses, trying 

 still to enter their nostrils and ears, and actually laying their eggs in 

 the latter of these organs, or perhaps in both. When they abound, 

 horses in woodland districts become very impatient at their work, 

 continually tossing their heads, and rubbing their noses at 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.'" Why it should ever deposit its eggs in the ear 

 of the animal seems unaccountable ; but Gilbert White was a most 

 accurate observer, as every one knows, and is therefore entitled to all 

 attention : still nothing is more curious than the instincts of the 

 CEstridas in depositing their ova. As regards the common ffi. Equi, 

 " the inside of the knee is the part on which these flies are most fond 

 of depositing their eggs, and next to this on the side and back part of 

 the shoulder, and less frequently on the extreme ends of the hairs of 

 the mane. But it is a fact worthy of attention," continues Bracy Clark, 

 " that the fly does not place them promiscuously about the body, but 

 constantly on those parts which are most liable to be licked by the 

 tongue ; and the ova therefore are always scrupulously placed within 

 its reach," and thus pass on to the stomach : and of OS. hoemor- 

 rhoidalis the same observer remarks, " the part chosen by this insect 

 for this purpose is the lips of the horse, which is very distressing to the 

 animal, from the excessive titillation it occasions, for he immediately 

 after rubs his mouth against the ground, his fore legs, and sometimes 

 against a tree ; or, if two are standing together, they often rub them- 

 selves against each other. At the sight of this fly the horse appears 

 much agitated, and moves his head backwards and forwards in the 

 air, to baulk its touch and prevent its darting on the lips ; but the fly, 

 watching for a favourable opportunity, continues to repeat the opera- 

 tion from time to time, till at length, finding this mode of defence in- 

 sufficient, the enraged animal endeavours to avoid it by galloping away 

 to a distant part of the field. If it still continues to follow and tease 

 him, his last resource is in the water, where the GKstrus never is ob- 

 served to follow him. At other times the Oestrus gets between the 

 fore legs of the horse whilst he is grazing, and thus makes its attack 

 on the lower lip: the titillation occasions the horse to stamp violently 



