DISEASES t)F THE POLL. 785 



that the seat of the lesions is the tendon common of the splenius, 

 or of the complexu's, or, perhaps, of the oblique or j)Osterior 

 straight muscles. 



At an advanced period, when the progress of the mortification 

 has been for some time unchecked, and the bony insertions of the 

 ligament, or of the tendons, have become affected, the surfaces of 

 these bones also become affected and their roughened or possibly 

 necrotic character is readily recognized by the exploring finger. 



It may also hai:)pGn that the capsular ligament of the joint, 

 constantly macerated in the pus, softens and yields, and the pene- 

 tration of the discharge into the vertebral canal soon ends the 

 ease by the rapid development of suppurative cerebro-spinal men- 

 ingitis. 



Hertwig and Lafosse have reported instances where anchylosis 

 of the occipito-atloid joint had taken place. 



There is in the museum of the American Veterinary College a 

 preparation of an anchylosis of the occipito-atloid articulation 

 which undoubtedly is the result of a case of chronic poll evil. 



The prognosis of this ailment is always serious. A slight 

 lesion may grow and develop into a case, with all its dangers. 

 For this reason a cautious expression of opinion on the part of 

 the surgeon is equally due to considerations of policy as to the 

 obhgations of truth. 



The treatment is essentially and exclusively surgical. 



In the simplest cases free oj)enings and ample drainage of the 

 wound, with plenty of washing and antiseptic attention will con- 

 trol the trouble. 



In more severe cases, where the presence of the fistulous 

 tracts is stimulated by the induration of the parts, and the con- 

 stant movements of their walls, the external application of a 

 strong blister and the injection into the fistulse of tincture of 

 iodine, or of cantharides, or of solutions, more or less concen- 

 trated, of tartar emetic, nitrate of silver, chloride of zinc, etc., 

 will contribute to immobilize the parts and stimulate the granu- 

 lating and healing process. 



The section of the cord of the ligamentum nuchae is indicated 

 when the tension of the region becomes too rigid, and the pain inor- 

 dinate. This alleviating measure was first instituted by Langen- 

 Ijacher and Hertwig in Germany ; then by Lafosse and Rey in 

 France, and it has always given excellent results. It relieves the 



