294 SECOND APPENDIX. 



then the two large teeth, called molars, begin to grow. "When 

 he reaches his fifth year he loses again two others in the same 

 way. Others grow in their place, which, hollow at first, begin to 

 fill up in the sixth year, so that when he is seven years old the 

 animal has his set complete. From that time on there are no sure 

 indications of age, only when the teeth project out of his mouth, 

 when his eyebrows are white, and when his hollow pits cave in 

 under his eyebrows, they suppose he is sixteen years old." Book 

 II, Cap. VII. 



This is an excellent description of the eruption and shedding 

 process, and the first clear description of the marks I have found. 

 Varro was a practical as well as a learned man. u The origin of 

 a horse," says he, " is a matter of the greatest importance, as 

 there are so many species." Again, speaking of veterinary science : 

 " The multitude of the maladies and the diversity of the symp- 

 toms render the science very complicated, and, to prevent mis- 

 takes, it is indispensable that prescriptions should be written." 



Columella (A. D. 42), says : u A horse may be broken for do- 

 mestic uses when two years old; but when intended for war he 

 must be over three years, so that he may not be exposed to it 

 before he has accomplished his fourth year. The marks by which 

 they distinguish the age of a horse change with his body. Thus, 

 when he is two years and a half old, the middle teeth upper as 

 well as lower fall off. Others grow again in the fourth year, 

 after those that are called canine or eye-teeth have fallen off. 

 Afterward the superior molars fall before the sixth year. In the 

 course of the sixth year those that have replaced the first ones 

 fill up, and by the seventh year all are full evenly. Afterward 

 they dig in, and the age can no longer be told with certainty. 

 However, at his tenth year his temples begin to cave in, his eye- 

 brows often become white, and his teeth protrude out of his 

 mouth. Book VI. Cap. XXIX. 



Columella, so far as I know, is the first to describe the shed- 

 ding of the molars. In Latin he says : " Intra sextum deinde 

 annum, molares superiores cadunt." (The Upper molars fall about 

 .the sixth year.) Like Varro and others, he says the teeth "fill 

 up, 1 ' a mistake that is common to this day. The cavities (marks), 

 unlike the pulp cavities, do not fill up with tooth substance they 

 are obliterated by wear. Of course they fill up with food. The 

 ancients were probably not aware of the fact that the wear of horses' 

 teeth is counteracted by the growth and the growth by the wear. 



