PATHOGENESIS 119 



explain at the present time. We believe, how- 

 ever, that infectious diseases such as influenza 

 or strangles play an important role in the 

 course if not also in the original cause. Where 

 influenza is rampant so will poll-evil and fis- 

 tula of the withers be found rampant. We are, 

 however, not today justified as laying this 

 down as an absolute law, as subsequent inves- 

 tigations no doubt may show that its cause 

 is more specific. 



