of the Animals of the Farm. 49 



old, aud it is absolutely necessaiy that he should inspect the 

 molars, in which impoi'tant changes occur between the ages of 

 fiiteen months and two years. 



Soon after the sheep reaches one ypar and a half, the sixth 

 molar begins to protrude through the gum. Shortly after- 

 wards the two anterior temporary molars give place to the 

 permanent teeth, and the third temporary molar is a mere shell 

 covering the top of the permanent tooth, which is coming up 

 beneath it, and pushing it out of its place, as shown in the 

 last illustration (Fig. 47). 



In this drawing the average condition of the molars of the 

 sheep just under two years is exhibited. The two anterior 

 permanent molars are cut, the third permanent molar is coming 

 up under the temporary tooth, which in many cases will have 

 fallen out, leaving the permanent organ to be seen below the 



Fig. 48. — Slv broad teeth at two years and three months. 



level of the other teeth. At the back of the jaw the sixth molar 

 is seen, but does not show any marks of wear, and this tooth, it 

 may be observed, affords the most valuable evidence at a critical 

 period. In the class " not exceeding two years," many of the 

 sheep are stated to be twenty months old, and some of the 

 animals may have the third pair of broad teeth not fully deve- 

 loped, but fairly advanced. When sheep exhibited as under 

 two years of age are found to have six broad teeth the animals 

 are naturally objects of suspicion, and further evidence is sought 

 for in the molars, which, as the drawing (Fig. 47) shows, exhibit 

 very characteristic marks at this period. Generally it may be 

 taken as a fact that if a sheep with six broad teeth shows the 

 three anterior molars in a state which proves that they are 

 recently cut, and especially if one or more of the temporary 

 teeth still remain, the age does not exceed two years. 



D 



