28 FISTULA AND POLL-EVIL 



cavities. In poll-evil it is the anterior part of 

 the funicular portion of the ligamentum 

 nuchge that prevents healing, while in fistula 

 of the withers it is the posterior end or its liga- 

 mentous continuation — the supraspinous liga- 

 ment — that is implicated. 



Cartilsiges of the Withers 



The cartilaginous tissue included among the 

 component parts of the withers is found in the 

 scaj)ular cartilage (cartilage of prolongation) 

 and in the semi-cartilaginous summits of the 

 dorsal spines. 



The scapular cartilage which is attached to 

 the vertebral border of the scapula is a wide 

 expanse of hyaline cartilage about two inches 

 wide extending from the cervical to the dorsal 

 angle. It is thick at the attachment to the 

 bone but becomes thin toward its vertebral 

 border which presents an evenly rounded pro- 

 file. Its mesial relations are the rhomboideus 

 and the serratus ventralis and its lateral the 

 trapezius and the attachment of the panniculus 

 carnosis. To these muscles it is intimately 

 related, being in fact imbedded in them. It 

 forms the lateral wall of many of the secondary 

 abscesses of fistula and its cervical angle and 

 sometimes its vertebral border becomes impli- 

 cated in the disease. By becoming divested of 



