1 66 Vetermary Medicine. 



tained good condition, glossy skin, elevated head, alert expres- 

 sion, keen sight and hearing, and normal breathing and pulse. 

 Standing in the stall there was no abnormal position of the limbs, 

 nor evidence of lack of perfect control. 



But when moved all this was changed. He showed first lame- 

 ness in the right fore limb and soon in all four members. The 

 feet were swung and planted uncertainly, the animal swayed and 

 staggered, the limb would knuckle over at the knee or fetlock, 

 or bend at the hock, and be recovered with diflfiiculty. After 

 going slowly for a few steps he moved with greater freedom 

 though still with difficulty, and the trouble was greatly aggra- 

 vated when the eyes were blindfolded. Then every step threat- 

 ened to precipitate him to the ground. The symptoms were es- 

 sentially those of locomotor ataxy. 



The tactile sensibility was unimpaired, the loins had the 

 normal sensibilitj', urination and defecation were natural and the 

 appetite remained good. After ten months he showed loss of 

 condition, dullness of the special senses, stupor, and a special 

 sensitiveness about the head, and resented its handling. 



Lesio7is. Thirteen months after the commencement of the at- 

 tack this horse was destroyed and the cord was found to be 

 profoundly altered by fibroid degeneration of the neuroglia and 

 absorption of the nerve elements (cells and fibres), the lesions 

 affecting different portions of the gray horns, and the columns — 

 superior, lateral and inferior. The affected portion of the cord 

 usuall}^ shows in man a grayish, opaque or translucent appear- 

 ance, with in some cases a shrunken a.spect and undue firmness 

 of texture, with at points, centres of softening. If hardened, 

 the .sclerosed sections take the carmine .stain deeply, but the 

 osmic acid or haeniatoxylin stain very slightly, contiary to what 

 holds in health. In recent cases there is onl}^ slight thickening 

 of the neuroglia, but when the disease is advanced the trabeculse 

 are thick, den.se, and firm, and the nerve fibres have largely dis- 

 appeared. The coats of the blood vessels adjacent to the .sclerosis 

 are thickened and their lumen is narrowed. Thickening of the 

 meninges is not uncommon, either confined to those covering the 

 diseased portion of the cord or extending completely around it. 

 Atrophy of the nerve roots is often appreciable by the naked eye. 



Diagnosis. Tliis depends largely on the fact that the condition 



