96 SOUNDNESS IN HOKSES. 



wear. In less frequent cases, the marks disappear earlier 

 than the generally accepted time. It is not a very rare 

 occurrence to observe that the mark has disappeared out 

 of the lateral lower incisors in a six-year-old animal. 

 These considerations render the " mark," of itself, any- 

 thing but a safe guide to the determination of a horse's 

 age. In Plate XXV., we may see the mouth of a nine- 

 year-old horse, whose teeth have retained all their 

 " marks." The roundness of the tables of the lower front 

 incisors, and, to a less degree, of the side ones ; the oval 

 appearance of the tables of the corner incisors; the 

 shortness and central position of the dental star; the 

 smallness of the central enamel of the lower front teeth, 

 and its closeness to the posterior edge of the table ; the 

 obliquity of the teeth, as viewed in profile ; and the 

 flatness of the dental arches, will afford unerring proofs 

 that the animal ought to be " beyond mark of mouth," 

 namely, over eight years. 



Ketention, for an unduly long period, of the apex of 

 the cone of the central enamel of the j)ermanent incisors, 

 gives a false appearance of comparative youth to the 

 mouths of some horses, as may be seen from Plate XXYI. 

 This, of course, occurs only after the cavity (or " mark ") 

 has disappeared ; and is due to the fact of the solid apex 

 of the cone of enamel being deeper than usual ; to the 

 hardness of the teeth themselves ; or, to some extent, to 

 the soft nature of the food. The form and degree of 



