40 MORE MINOR HORRORS 



cattle being comparatively immune. The in- 

 explicable terror which the warble-fly induces 

 in its victims is testified to on all hands, but 

 has never been adequately explained. Hypo- 

 derma does not bite, neither does it sting. 



Fig. 12. — Cow being chased by fly. Note terrified 

 look of eyes. (From Hadwen.) 



Many other blood-sucking insects,, whose punc- 

 ture must involve some pain, are tolerated 

 by cattle with a flick of the tail, or are fright- 

 ened off by a gesture of the head ; but the 

 presence of the warble-fly induces a mysterious 

 fear which rapidly spreads through a herd, 

 and results in a general stampede — often 

 referred to by cattle-breeders as the ' gad.' 

 This terror communicates itself even to the 



