132 DADD'S VETERINARY MEDICINE AND SURGERY. 
become blunt, less angular, and more rounded, and the furrows 
have disappeared. Supposing that the tushes are not completely 
evolved until the age of five; in the sixth year the apex of the 
cone is worn some; in the seventh the furrows grow shallow; in 
the eighth year they are obliterated, after which period the apex 
gradually wears away, and the body of the same becomes rounded 
and pointed, or blunt, according to circumstances. Aside from 
the teeth, an aged horse may be known by the deep pits above the 
orbital processes; the sunken eye ; by the prominence of the joints 
and loss of plumpness in the muscles; the lips are somewhat pen- 
dulous; the withers sharp; the back becomes arvled; the teeth 
are lengthened, and become yellow. 
Fig. 12. 
A POBTIO™ OF THE UCHPER JAW OF OLD BLACK HAWKE, 
(Aged twenty-three years and eight munths.) 
THE GrinpeErs, or Mouars, afford but very little informanwe 
ag regards the precise age of a horse. As he advances in yeera 
however, the outer edges become sharpened, so that it often Le 
comes necessary to rasp them. As regards their development, is 
is understood that the foal is born with two upper and lower 
grinders in each jaw. At the end of a month, sometinies more, 9 
third appears. At the completion of the first year, or thereabouts 
a fourth grinder in each jaw appears. Thus the yeailing has six- 
teen grinders. At the age of two, a fifth grinder appears, and at 
the age of three the sixth and last appear. It must be remembered 
that cribhers and voracious feeders are apt to deface their teeth, 
and thus some persons are apt to be deceived as regards the exact 
age; but a good judge, who takes into consideration not only the 
appearances of the surfaces, but also the marks, points, and the 
inclination of the teeth, will not be apt to make any grave mistake 
