408 INSECT ARCHITECTURE. 



deposit her eggs upon the hair, and as insects of the 

 same genus almost invariably proceed upon similar 

 principles, however much they may vary in minute 

 particulars, it may be inferred with justice, that the 

 breeze-flies which produce galls, do the same. The 

 description given by Mr Bracey Clark, of the pro- 

 ceedings of the horse breeze-fly, is exceedingly in- 

 teresting. 



" When the female has been impregnated, and her 

 eggs sufficiently matured, she seeks among the 

 horses a subject for her purpose, and approaching 

 him on the wing, she carries her body nearly upright 

 in the air, and her tail, which is lenglhened for the 

 purpose,* curved inwards and upwards: in this way 

 she approaches the part where she designs to de- 

 posit the egg; and suspending herself for a few 

 seconds before it, suddenly darts upon it and leaves 

 the egg adhering to the hair; she hardly appears to 

 settle, but merely touches the hair with the egg held 

 out on the projected point of the abdomen* The 

 egg is made to adhere by means of a glutinous 

 liquor secreted with it. She then leaves the horse 

 at a small distance, and prepares a second egg, and 

 poising herself before the part, deposits it in the same 

 way. The liquor dries, and the egg becomes firmly 

 glued to the hair; this is repeated by these flies till 

 four or five hundred eggs are sometimes placed on 

 one horse." 



Mr Clark farther tells us, that the fly is careful to 

 select a part of the skin, which the horse can easily 

 reach with his tongue, such as the inside of the 

 knee, or the side and back part of the shoulder. It 



* These circumstances afford, we think, a complete answer 

 to the query of Kirby and Spence, — " There can be little 

 doubt, (or else what is the use of such an apparatus?) that it 

 bores a hole in the skin." — Introd., i. 162, 2nd. edit. 



