8 INTRODUCTION 
nation of its cause. Thus years have been 
wasted in attacking the disease from without, 
giving only casual attention to the “interior” 
of the withers where it actually originates. 
We do not insist that the names “‘fistulous 
withers” or “fistula of the withers” are even 
good appellatives for the disease we are about 
to describe. On the contrary, a name less spe- 
cially pathologic in its meaning would seem 
more appropriate, since fistula is but a phase of 
the entity as a whole. The name, inappro- 
priate as it is, we retain because among our 
American readers it has been consecrated by so 
many years of usage that a change would lead 
to no better understanding of our exposition or 
argument. We retain the name, therefore, 
with the full knowledge that it is appropriate 
only for the latter stages of the disease and that 
the fistule are but msignificant parts of the 
total pathogeny. 
Poll-evil, which we argue is but the same 
condition attacking the atlantal bursa, has, on 
the contrary, been more extensively described 
by writers throughout the history of modern 
veterinary science, and although it had been re- 
ferred to always as a complication of a trauma- 
tism in the earlier days, it was the first of these 
two diseases to be recognized as a bursitis. It 
has been designated as inflammation of the 
