130 DISEASES OF THE HORSE. 



Who has not seen scruffy or scaly heels of horses 

 ending with scratches ? (See Skin Diseases.) 



Mange. — Is a disease of the skin, and is caused by a 

 small mite called acari, which breed and burrow in the 

 skin. To cure mange, destroy the insect. (See Skin 

 Diseases.) 



Materia Medica. — This is a name used or applied to 

 every substance used in the treatment and cure of disease. 



Megrims- — A disease of the brain occurring at pe- 

 riods, especially in hot weather, and when exposed to a 

 powerful sun. This differs from epilepsy only in the ab- 

 sence of spasms. (See Epilepsy.) 



Causes. — Tumours in the choroid plexus, and enlarge- 

 ment of the pineal gland. 



Treatment, — Merely palliation, by using a dutch collar, 

 80 as not to interfere with the circulation of the blood 

 from the head. 



Observe. — In summer, the horses subject to brain di- 

 sease, or fits of any kind, should not be used for family 

 purposes. In winter they will make useful animals. 



Melanosis- — A variety of cancer peculiar to gray 

 horses, which turns white with age, and is caused by the 

 transfer of the coloring pigment from the skin to the 

 blood. (See Cancer.) 



Melanoid. — (See Cancer and Tumours.) 



Mesentery- — A membrane formed of two folds of 

 the peritoneum, and between each there are numerous 

 glands, lacteals, lymphatics, arteries, veins and nerves. 

 It is called the mesentery, because it adheres to three 

 lumbar vertebrae, and has the small intestines hanging to 

 it. One portion of it is called the mesocolon — supporter 



