14 
conducive to health; and we have proof of this in the 
deaths of attacked animals from consequent internal 
inflammation. But here I am on points outside my 
own department. I have mainly entered on the life- 
history of this special attack for the sake of comparison 
with the less studied history of the kind I am now 
going on to. 
WARBLE FLY or OX BOT FLA. 
Ox Warble Fly. 
The attacks of the Ox Bot Fly or Warble Fly, the 
(Estrus ( Hypoderma ) bovis, DeGeer, may be taken scien¬ 
tifically as a good example of the division of the Bot 
Flies that infest the hide. Practically and financially 
the subject is of enormous importance, not only on 
account of the suffering and waste of forces of the cattle 
caused by the attack, but also from the direct loss in 
value of warbled hides. In a letter (published in 
December, 1880) by Mr. W. H. Liddell, who is well 
qualified to express an opinion on this subject, he 
observes:—“There are at present, I may safely say, 
three-fourths of all our cattle being tortured by this in¬ 
veterate insect, which, by a little trouble and at a nominal 
expense, could be extirpated; and thus we should save 
an immense amount of capital and wipe out a disgrace 
to all who neglect their cattle.” 
From experiments and information sent in during this 
year it appears to me that the attack might be put an 
end to, and any damage to the hide (save what would 
soon heal durably and reliably) might be escaped by the 
simple plan of dressing each of these maggot-infested 
