176 



That the jagged-sided channel (not smooth-sided as it would be if pierced by an 

 €gg-laying tube) leads in a slauting or straight or curved direction from a little open- 

 ing at the bottom ; * * * also I have found the tunnel partly cut down from the 

 outside, and I have found a small, soft body in it. 



The injury occasioned by the presence of these grubs to hides and 

 the diminished quantity and inferior quality of the beef and dairy prod- 

 ucts were perhaps sufficiently indicated in our notes on this subject in 

 the last number of Insect Life. 



The value of the application of various oils both to prevent the ovi- 

 position of the fly, and especially to destroy the larvse, has been long- 

 known ; and, aside from the discovery that certain substances are more 

 effective than others, little has been added to our knowledge of reme- 

 dies of late years. Clark, in the articles already cited, fully indicates 

 the good of such applications, and states that Pliny, who was acquainted 

 with these flies, " has recommended for protecting animals from their 

 attacks to annoint them with fats and oils. ; ' 



In our article, which we have already quoted at length, the use of 

 kerosene was particularly recommended to destroy the larvae, as well 

 as to deter the fly from ovipositing. In the discussion of remedies by 

 Miss Ormerod, in her various reports, a number of strong-smelling oils 

 are recommended, with which to smear the animals' backs to protect 

 them from the fly. Of these, train-oil or fish-oil — the same that has 

 proved of advantage against the Buffalo Gnat in the South and recently 

 against the Horn Fly in Virginia and Maryland — has been especially rec- 

 ommended. A similar application is the simplest and easiest method 

 of destroying the warbles, which it does by closing the breathing pores 

 on the posterior end of the body. The destruction of the larva3 in this 

 way may be effected by one or two applications in autumn, and is the 

 most satisfactory method of controlling this pest. The appearance of 

 the flies during the entire summer renders operations against these dif- 

 ficult and expensive. 



Additional means of protection against the flies are : the use of kero- 

 sene emulsion, rancid butter or tar-oil mixed with sulphur, or dry sul- 

 phur alone ; against the grubs, any of the oily preparations mentioned 

 above, and in addition, the placing of a small quantity of mercurial 

 ointment on the hole in the skin, or of spirits of tar, or carbolic acid ; 

 finally, piercing the grub with some sharp instrument or removing it 

 by pressure. * 



This condensed account of what is known of the habits of this Bot 

 Fly is given partly in compliance with an earnest request from Mr. 

 Alexander, of the Farmers 1 Review, that we take up the question, and 

 partly with a view of showing how little there is to be done by the 

 Department of Agriculture except by extending the inquiry in sta- 

 tistical lines somewhat similar to those followed by him. Even admit- 

 ting that some more careful observations might be made bearing on 

 the actual mode of oviposition and duration of the egg state, these are 

 points of biologic interest rather than of economic importance. 



