POLL-EVIL 109 
neath which lies the spinal cord unprotected 
by bony covering. Above the intervertebral 
ligament there is a thick musculature and the 
funicular portion of the ligamentum nuche. 
The occipito-atlantoid articulation is a diar- 
throsis whose large capsular ligament is ar- 
ranged to include both occipital condyles. It 
is protected superiorly by muscles which also 
separate it from the ligament laterally. 
The atlantoid bursa—the initial seat of al- 
most all poll-evils—lies between the ligamen- 
tum nuche and the dorsal arch of the atlas. 
This bursa has no connection with the articu- 
lation. 
The spinal cord is exposed in two places to 
both the disease and the operation against poll- 
evil. It is, however, in the atlanto-axoid space 
that it is most likely to be encroached upon. 
The musculature covering it in the atlanto- 
axoid space or the intervertebral ligament, is 
usually the floor of the abscess cavity but some- 
times these structures are degenerated and per- 
forated in a downward direction until first the 
meninges and later the cord becomes involved. 
The cord exposure in the space is about one 
arid a half to two inches. The cord must also 
be thought of when packing wound cavities 
with hemostatic packs because its covering is 
compressible and considerable spinal pressure 
