100 FISTULA AND POLL-EVIL 
the shoulder. ‘This proved to be a typical cold 
abscess involving these lymph nodes. 
Fistula Caused From Collar Sitfasts 
There is a type of fistula that differs some- 
what from those just described. It is located 
in front of the generally accepted limits of the 
withers proper, and it exhibits certain etiologic, 
pathologic and clinical differences that call fo: 
a special description and which require differ- 
ent methods of management. 
This injury starts as a cutaneous collar le- 
sion. It begins as a pressure necrosis of the 
skin alone but later involves first the pad of the 
mane and then the funicular portion of the 
ligamentum nuche and even extends down- 
ward into the lamellar portion, creating a very 
troublesome condition to treat. 
When observed in the early stage of devel 
opment, the seat of the collar at the level of 
the mane where the thick skin is folded trans- 
versely into several deep undulations, is found 
to contain a black, smooth, hairless. leather- 
like, circular zone of insensitive integument 
that is loosened slightly from the viable skin 
all around its cireumference, but which can not 
be lifted off. It is attached and although some 
time is given for it to separate, no such an event 
occurs. It remains stubbornly attached. At 
