of the Animals of the Farm. 19 



nearly together, so that eight molars are cut between the second 

 and third year. 



At two years and a half old, one or two of the permanent 

 molars may be in the mouth. Sometimes the second in position 

 is cut before the first, and a careful examination will show that 

 the crowns of the first and second temporary molars which yet 

 remain are only retained in their position by a slight attachment 

 to the gum, and very little force is required to dislodge them. 



The drawing on p. 20 (Fig. 11) shows the condition of the 

 molar teeth soon after two years and a half. A permanent 

 tooth, the first in position, is seen occupying the place of the 

 temporary molar which has fallen, and the second permanent 

 tooth is pushing its way up under the second temporary molar, 

 which is only held in its place by small portions of the fangs 

 that have not yet been absorbed. The fifth molar, which was 

 up at two years old, is fully developed, and is quite clear from 

 the angle of the jaw. 



At three years old the first and second permanent molars 

 are well up, and the top and bottom teeth are in contact when 

 the mouth is closed ; but the teeth are distinguished by the 

 recent appearance which they present in comparison with the 

 worn surfaces of the teeth immediately behind them. 



From the completion of the third year to the termination 

 of the fourth year, the changes which have been described in 

 reference to the central incisors and the first and second molars 

 occur in the lateral incisors, and the third and sixth molars. 



At three years "off" the same condition of the gum which 

 was described in respect of the upper central temporary incisors 

 now appears at the necks of the lower lateral temporary incisors. 

 At three years and a half some, or perhaps all four, of the per- 

 manent lateral incisors are in the mouth ; and soon afterwards 

 the third and sixth permanent molars are cut, as shown in the 

 drawing (Fig. 12, p. 20). 



No diflficulty would be experienced in distinguishing the 

 recent molars in the condition represented in the illustration. 

 The first and second, and the fourth and fifth molars show con- 

 siderable wear, while the new teeth present rounded points on 

 their surfaces, and are not nearly level with the other teeth. 

 One or two of the most projecting points of the sixth molars 

 show the effects of attrition ; but these teeth at the age of three 

 years and a half have their posterior points close to the angle of 

 the jaw and still covered with the gum. 



At four years old the horse has the lateral permanent in- 

 cisors in apposition, and the third and sixth molars are level, 

 or nearly level, with the other teeth. 



B 2 



