THE WITHERS 23 



supraspinous ligament, each of which is but a 

 continuation of the other; the dorsoscapular; 

 and the interspinous hgaments, which curtain 

 off the spaces between the spinous processes. 



The hgamentum nuchge is a strong, powerful 

 apparatus conij)osed of yellow elastic tissue and 

 divided into two distinct parts: the funicular 

 portion and the lamellar portion. The former 

 which is of especial importance in fistula of the 

 withers and poll-evil, extends from the occip- 

 ital bone anteriorly to the summit of the 

 withers posteriorly where it becomes white 

 fibrous tissue and is continued over the spines 

 of the sacrum as the posterior part of the sup- 

 raspinous ligament. It is composed of two 

 lateral halves each of which is heavy and 

 flattened at the withers but gradually becom- 

 ing round and somewhat smaller toward the 

 occipital crest to w^hich it is attached to the 

 occipital protuberance. Two bursge are 

 found associated with this structure — one 

 at the atlas and the other in the dorsal region. 

 The atlantal bursa is the seat of poll-evil while 

 the dorsal or supraspinous bursa is the location 

 of typical fistula of the withers. The atlantal 

 lies between the ligament and the dorsal sur- 

 face of the atlas. Tlie dorsal bursa is usually 

 over the third dorsal spine but sometimes ex- 

 tends backward as far as the crest, that is, over 



