DETERMINING THE AGE OF ANIMALS 195 



triangular, and the dental star appears as a dark round spot in 

 both the nippers and dividers. 



Fifteen Years. — The angle with which the teeth meet is 

 greater than at twelve, the teeth are smaller and dental stars 

 are represented by dark round spots in all of the inferior incisors. 

 The tables of the nippers and dividers are triangular. 



Seventeen Years. — All of the tables of the lower incisor 

 teeth are triangular. The teeth are narrower and smaller than 

 at fifteen. The profile of the incisors, viewed from the side, is 

 quite aniiiilar. The dental stars are prominent. 



Nineteen Years. — All of the signs of the seventeen-year-old 

 mouth are more prominent. The cups have usually disappeared 

 from the upper incisors. 



QUESTIONS 



1. Name the different kinds of teeth; state the arrangement and number. 



2. How is the age of an animal determined? 



3. Give the time of replacement of the temporary incisor teeth. 



4. How is the age of the animal determined between the fifth and ninth 



years? 



5. \Miat changes in the appearance of the table surfaces occur between 



ten and fifteen years of age? 



