EXTERIOR. 47 



orifices of the aerial passages which directly communicate 

 with the lungs, and indeed it is by them alone that the air 

 penetrates to the respiratory organs. These soft, dilatable 

 orifices undergo considerable expansion, at the same time 

 becoming more circular in order to accelerate respiration 

 in rapid gaits, and they again contract to their normal 

 condition. 



A fine and very mobile nasal aperture is generally 

 found with a broad face and capacious forehead. 



The nostrils (9, fig. 26), by the variation of confor- 

 mation in the soft skin which surrounds them, form a 

 considerable addition to the animation of the head. They 

 palpitate when the animal is under the influence of fear 

 or anger. The movements of the end of the nostrils and 

 of the upper lip herein participate. 



The end of the nostrils (10, fig. 26), the limitation of 

 w r hich is not rigorously defined, is between the nostrils 

 and the lower lip. It is mobile and sensitive ; in well- 

 bred horses it is firm and prominent. 



The lips should be thin, with a fine skin. The mouth, 

 which to be attractive should be limited by them, ought 

 to be moderately cloven, and betray all the sentient 

 impressions of the animal by its excessive mobility. 



The relaxation of the lips, more especially of the 

 inferior, indicates age, especially if laxness permits the 

 elongation of the teeth to be visible. 



The chin, a rounded and wrinkled prominence, forms 

 part of the lower lip, just as the end of the nostril is 

 connected with the upper. 



The fleshy portion, covered with hair, visible below 

 the mouth, behind the chin, is designated as the barb. It 

 is against this that the curb of the bit makes itself felt. 



The. jaws (12, fig. 26), which should not be massive, 

 are situated on the two sides of the jaw bone. The osseous 

 branches, reuniting to form them, constitute an angle 

 called the inferior maxillary (13, fig. 26). The sides 

 should be wide open so as to allow ample space for the 

 first rings of the tracheotic artery, which forms the base of 

 the throat. 



Remarks. — On examination of the works of the old 

 masters one is forcibly impressed by the little care which 

 even the best artists bestowed upon the reproduction of 



