78 Veterinary Medicine. 



tated. This variability of symptoms is suggestU-e of parasitism. 



While turning around in a circle has been already noticed 

 there remains, in certain cerebral forms, the peculiar phenome- 

 non of the animal rotating rapidly on its longitudinal axis. The 

 patient falls on its side and rolls over and over. Among the 

 brain lesions with which it lias been experimentally identified are 

 injuries to the middle peduncles of the cerebelhun, or of the siipero- 

 external portion of the cerebral pedinicles, or of \.\\& posterior pai't 

 of the encephalon , or of different parts of the hemispheres. 



Cases of vertigo that occur without any appreciable lesion have 

 been named essential vertigo. Guibert has attributed some cases 

 to irritation of the lower part of the limbs by contact with the 

 litter but this could only occur in an animal in which the nervous 

 system was in a morbidl}' excitable condition. 



Treatment. The prophylactics and therapeutics of vertigo 

 will vary with the cause. The diagnosis of the cause is there- 

 fore the most important step. In pampered, overfed, idle horses 

 a reduced ration and daily exercise or work will often suffice. 

 It is usually desirable, however, to remove intestinal irritants 

 and deplete the vascular system by an active purgative. If the 

 attacks appear only in Spring this care should be especial!}' given 

 at such seasons. A tight or badly fitting collar should be cor- 

 rected, also a position of the breast .strap which causes it to press 

 on the jugular veins. A short bearing rein causing undue 

 flexion of the head must be lengthened or abandoned. A too 

 dark stable should be avoided, also the sudden exposure to white, 

 dusty roads and, still more so, to the glare of snow, ice, or 

 water. A short, overdraw check rein, turning the eyes up 

 directly into the sun's rays, or blinds with a glistening iniief sur- 

 face may require correction. It may be better to abandon blinds 

 altogether, or to cover the eyes by a piece of leather, 2 to 4 

 inches wide, extending across the forehead from one eye to the 

 other ; or a sunshade attached to the headstall ma}' be worn .so 

 as to protect the eyes. Horses which become seasick or carsick 

 may .sometimes be helped by covering the eyes. Other indica- 

 tions would be to treat any existing trouble which interferes with 

 a normal circulation in the brain (pulmonary congestion, aneu- 

 risms, tumors pressing on carotids or jugulars, phlebitis, etc.), 

 and such as affect the ear (disease of the pharynx, guttural 



