Diseases of the Nervom System. 249 



cutting the nerves proceeding from this part, or better by 

 light firing with an iron at a red or white heat. 



CHOREA. ST. VITUS'S DANOE. ST. GUY'S DANCE. 



Mainly seen in the dog and horse. Occurs in subjects 

 debihtated or worn out by disease, as in dogs by distem- 

 per. There is no constant structural change in the braia, 

 but the occurrence of the disease as a consequence of 

 exhausting disorders and the excess of urea, etc., in the 

 urine, may be taken as implying an altered state of the 

 blood, and of the processes of sanguification. 



Symptoms. Momentary spasms of the voluntary mus- 

 cles, leading to jerking of one or more limbs, of the head 

 or of the entire body. This continues without intermission 

 in sleep as in waking, and, by wearing the subject out, 

 increases the disorder. In the horse it occurs mainly in 

 the hind limbs, but will also attack the fore, and tempora- 

 rily the muscles of the body. 



Treatment. Re-establish health and vigor by abundant 

 nourishment, open air exercise, tonics (sulphate and car- 

 bonate of iron, cascarilla, quiaiaj cold baths, rubbing dry 

 afterwards, and strychnia. Nerve sedatives (chloral-hy- 

 drate) may be given to cheek or moderate the spasms. 



VERTIGO. MEGRIMS m HORSES. 



An equine disease characterized by sudden and tempo- 

 rary loss of sensation and voluntary motion, with trem- 

 bUng, and it may be champing of the jaws, but without the 

 general spasms of epilepsy. 



Causes. Brain disorders such as tumors, congestions, 

 effusions, etc., or modified circulation from compression 

 of the jugular veins, or disease of the heart. Plethora is 

 a frequent cause in the young. 



Symptoms. The animal drawing a load, especially vTp- 

 hill, with a tight collar, driven hurriedly in extreme heat, 

 or in a strong glare of sunshine or snow, suddenly hangs 

 on the reins, slackens his pace, staggers a little perhaps, 



