e>2 



DIGESTION AND FOOD. 



tushes appear of considerable size. The deciduous molars 

 are likewise shed at one year, and succeeded by permanent, 

 " At eighteen months/' says Professor Simonds, " or about 

 this period, the dentition of the pig may be said to be com- 

 pleted. This is effected by the cutting of the lateral incisors, 

 and also of the last or sixth molar." Professor Simonds fur- 

 nishes us with the following useful table : 



I have referred to the subject of age in connection with 

 the process of dentition in our domestic quadrupeds, and it 

 may not be inappropriate to allude to the fact that other signs 

 indicate youth, adultism, and old age. In horned animals 

 the horns grow annually a certain length,, and this is shown 

 by the appearance of an extra ring every year at the root of 

 the horn. For the first two years the rings are so indistinct 

 that in calculating the age in an animal five or six years old, 

 the first ring indicates a three years' growth, so that an animal 

 with six rings in its horn must be regarded as eight years 

 of age. 



Fraud has been practised to destroy the marks of age. 



