THE WITHERS 17 
is to the summit. Along the region of the with- 
ers its fibers, unlike those of any other part of 
the body, are vertical, extending downward to 
the proximal border of the scapular cartilage, 
where they find another fixed attachment. It 
is fused with and in fact may be regarded a 
part of the superficial fascia. As a structure 
to incise for invasions into the withers it may 
be so considered. Beneath the superficial fas- 
cia is another aponeurotic layer whose fibers 
are so arranged as to cross those of the tra- 
pezius beneath at right angles. This layer is 
of no special surgical importance. It is found 
only in a careful dissection of the region and is 
in no way influential in guiding pathological 
processes nor in shaping surgical procedure. 
The Trapezius 
The trapezius, excluding the fascia just 
mentioned, is the third layer of the withers and 
is really the first of the anatomical structures 
that must be reckoned with in the study of fis- 
tula. It is a triangular membranous muscle 
with its base upward running along the withers 
where its aponeurosis is attached to the supra- 
spinous ligament along the withers and to the 
ligamentum nuche in the cervical region, ex- 
tending in all from the axis to the tenth dorsal 
vertebra. This triangular sheet-like structure 
