410 



INSECT ARCHITECTURE. 



sue him. These flies appear sometimes to hide them- 

 selves ill the grass, and as the horse stoops to graze 

 they dart upon the mouth or lips, and are always 

 observed to poise themselves during a few seconds 

 in the air, while the egg is preparing on the extended 

 point of the abdomen.''^* 



The moment the second fly just mentioned touches 

 the nose of a sheep, the animal shakes its head and 

 strikes the ground violently with its fore-feet, and at 

 the same time holding its nose to the earth, it runs 

 away looking about on every side to see if the flies 

 pursue. A sheep will also smell the grass as it goes, 

 lest a fly should be lying in wait, and if one be de- 

 tected, it runs off in terror. As it will not, like a horse 

 or an ox, take refuge in the w ater, it has recourse to a 

 rut or dry dusty road, holding its nose close to the 

 ground, thus rendering it difficult for the fly to get 



at the nostril. 

 When the 



eeze fly (^Hijpodcrma 



a The. bellv of the gnib. h Its back, c Tlie tail of the grub, 

 greatly magnified, d The biiinp, or gall, having its extcriial 

 aperture filled with the tail oi" the grub. 



* Linn. Trans, iii. 305. 



