90 THE HORSE 



approximating age in horses by a reference to a groove 

 making its appearance in the upper corner incisors at the 

 base of the tooth, that is, at its junction with the gum. It 

 makes its appearance at ten years and is about half-way 

 down the tooth at fifteen and extends the whole length of 

 the tooth at twenty-one. By the time the animal is 

 twenty-five years of age this groove becomes effaced 

 next to the gum but extends from the middle of the tooth 

 down to the cutting edge, whilst at thirty years it is 

 situated very close to the cutting edge. 



With regard to the molar teeth, the first, second, and 

 third molars in each jaw are only temporary, whilst the 

 fourth, fifth, and sixth are permanent. The first-named 

 three teeth occupy the front position in the jaws, but none 

 of these are replaced before the fourth molar has made its 

 appearance. 



The reader will receive some assistance in the foregoing 

 description of the teeth b}^ reference to the accompanying 

 illustrations, but he should in every instance supplement 

 this by a practical appHcation of the knowledge thus 

 acquired, as nothing in connection with animal dentition 

 could possibly be truer than the old adage, *' An ounce of 

 practice is worth a pound of theory" — in other words, 

 " Knowledge increaseth practice and practice increaseth 

 knowledge." 



