iiy 



tail being the longest and strongest on the body. Those which form the 

 ■"foot locks" are peculiar to the horse, and vary in length and coarseness 

 with the breed of the animal. When hair is fine and long and wavy, it forms 

 wool ; and when straight and rigid, as in the pig, it is known as bristles 

 (Chameau). 



The sweat glands arc very numerous over the surface of the body. 

 They consist of small lobular masses formed of a coil of a gland tube 

 surrounded by little blood vessels, and embedded in fatty tissue in or 

 beneath the derma. From the coil passes a duct, which opens on the 

 surface of the skin. According to Erasmus Wilson, there are as many as 

 3,528 glands on each square inch of the palm of the hand of a man, while on 

 the neck and back they only amount to 417. Tlie total number of these 

 glands in the human being is estimated at nearly two and a half millions. 



MANGE. 



After these few preliminary remarks, we may at once proceed with the 

 consideration of the symptoms and treatment of the various maladies of 

 the skin of the horse. W^e shall first devote our attention to the parasitic 

 •diseases. These fall into two main groups, viz., those due to animal parasites, 

 and those due to vegetable parasites belonging to the order of the fungi, 

 such'as the various kinds of ringworms. 



Mange or scab is an affection of the skin, decidedly contagious, caused 

 by the presence of little creatures belonging to the same order as the 

 mites. These little animals are of three varieties in the horse, 

 but' do not differ very much in appearance or size. The "scab" acari of 

 slightly"'differing kinds infest man and all the domesticated animals. These 

 parasites are said to live on the fluid, which is effused from the blood, owing 

 to the irritation their presence sets up. 



The first kind which infests the horse, termed dermatodectes equi, of 

 which we append'a drawing, is the kind most frequently met with in England; 

 This creature causes the formation of little elevations on the skin, in the 

 upper part of which the contents soon become liquid and burst, and 

 afterwards becoming drier, form crusts or scabs. These little elevations or 

 pimples, which are about an >sth of an inch in height, are especially 

 numerous on the upper part of the neck and root of the tail. If a few crusts 

 be.^taken off, placed on a white surface, and exposed to the heat of the sun, 

 the parasites may easily be discerned with a small magnifying glass. The 

 itching^which is set up by these creatures is of an intense character. They 

 deposit a^ secretion of great acridity, and by their long mandibles or jaws, 

 theyTcause 'serious alterations in the skin, which is rendered bare, wrinkled, 

 .and bleeding, especially around the mane. The disease occasioned by them 

 is 'more' amenable to treatment, and spreads much more slowly than that 

 produced by the second variety. The greater facility v^ith which these 

 creatures can be killed by the application of ointments, is no doubt due to the 

 fact that theyldo not burrow into the skin, but merely conceal themselves 

 ■imder and among" the scabs. The dermatodectes Vwe in colonies. 



