CHAPTER XIX 



DETERMINING THE AGE OF ANIMALS 



General Discussion. — The teeth are the passive organs of 

 digestion. They are hard organs, implanted in the superior 

 and inferior jaws in the form of a long and narrow arch that is 

 open posteriorly. The free portions of the teeth project into 

 the mouth, and present sharp or roughened table surfaces for the 



Fig. 51. — Head of young horse with bone cut away, and showing position and size of teeth. 



crushing and tearing of food. In solijieds and ruminants the 

 arch is interrupted on each side by the inter-dental space or bars 

 (Fig. 51). The teeth that form the middle and anterior por- 

 tion of the arch are termed incisors (Fig. 52). Posterior to the 

 incisors are the canines or tusks, and fonning the arms of the 

 arch are the molar teeth. Animals have two sets of teeth, tem- 



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