HORSE WARBLE FLY. 77 



investigations on Ox Warble to Mr. John Dalton, Wigtou, Cumber- 

 land, may be of interest as explaining (in connection with the above 

 observations) why traces of warble-presence are so little noticed on 

 horse hides : — 



" With regard to your question about warbles in horses, I can give 

 you but little information. Of the horse-hides I get, I should say not 

 one in fifty is warbled, and the appearance of the hides when tanned 

 shows that warbles are of rare occurrence; there is no cicatrix as in 

 cattle, and when a warble does exist, it is a single one, and never, so 

 far as I have seen, in numbers. As horses are not used for food, the 

 hides are comparatively scarce, and only a few — and those mostly old 

 ones — come under the observation of the tanner. I never remember 

 seeing more than one warble-hole in a horse-hide ; I mean in any 

 single hide. Whether it is the same species of warble as in the ox, I 

 cannot give an opinion ; I am inclined to think it is the same, . . . but 

 this is of course mere supposition." 



In regard to presence of warble in imported hides, Mr. Dalton 

 wrote: — "Horse-hides are imported in large numbers from South 

 America ; the Spaniards rear horses in immense quantities, and kill 

 them for the hides and feet. They are slaughtered at two or three 

 years old, and these hides are quite free from warbles." 



The great number of warble-maggots found by Mr. S. Hall on his 

 mare seems to open up still more than before the question whether 

 the attack may not be at least sometimes of our common Ox Warble 

 Fly. Any way, it would be very desirable to have more certain know- 

 ledge on the subject, and if any of those into whose hands this paper 

 may come would favour me with specimens of the maggot which they 

 may have squeezed out when near maturity, I should be very glad of 

 the opportunity of investigating the characteristics, describing, and, if 

 possible, figuring it. 



If circumstance allowed of the maggot not being removed, so that it 

 might drop out when ready for its change, I would most gladly on 

 application describe the very easy way in which it might be secured so 

 as to give us a chance of rearing the fly. 



