74 THE EXTERIOR OF THE HORSE. 



them into their alveoli is called the gums'. These offer little of interest. 

 In young horses they are rosy, thick, and adherent, but as the animal 

 grows older they become pale and retracted from the teeth. Alimen- 

 tary matters may penetrate between their dental surface and the teeth, 

 excite inflammation, and become the origin of periostitis or of caries 

 of the bone. 



3. The Bars (Figs. 25 and 26). 



Situation ; Limits ; Anatomical Base. The bars, occupying 

 the inferior interdental space on each side, include that portion of the 

 inferior maxilla between the canine and first molar teeth, and are 

 covered simply by the mucous membrane. In the mare, in which 

 the tushes are undeveloped, the bars are longer, and extend from 

 the corner incisor tooth to the first molar. They support the canon of 

 the bit, 



Most authors have pretended that the conformation of the bars is of 

 great importance relative to the pain which the horse feels as a conse- 

 quence of the pressure of the bit ; that if they be elevated or sharp, the 

 pain is intense, and, on the contrary, feeble when they are round ; finally, 

 that the form of the bit should be adapted to the one or the other of these 

 dispositions. We repeat here what we have already said above as to 

 the bars : with equal sensibility it is certain that on the sharp bars the 

 pressure will be more intense, but the difference which we observe in 

 the sensibility to the action of the bit resides not so much in the con- 

 formation of the parts as in the natural sensibility and irritability 

 themselves, all peculiarities of this region. As M. Sanson * has justly 

 said : when sharp bars accompany a nervous and irritable temperament, 

 it is to this alone that & false or spoiled mouth, as well as the faults of 

 rearing or running away, must be attributed. Most horses whose 

 mouths have been abused with the bit by inexperienced riders or 

 drivers present round and depressed bars. When the mucous mem- 

 brane is thickened and the sensibility is blunted, they are called calluses. 



The bars may be the seat of wounds sufficiently grave to prevent 

 the use of the animal for a variable period of time. Due to forcible 

 traction on the bridle, these may terminate in caries, fistula, and exfoli- 

 ation of a part of the bone which forms their base, and leave a perma- 

 nent deformity. 



To recapitulate, the fineness of the bars constitutes the principal 

 beauty to be sought for in their examination. 



1 A. Sanson, Nouveau Dictionnaire pratique de mdecine, de chirurgie et d'hygiene vt<*ri- 

 naires, t. ii. art. " Bouche." 



