ALTERATIONS DURING THE FIRST YEAR. 177 



MOLARS. 



The molars, except for their smaller size, resemble those of 

 the ox. They gradually increase in size from the first to the 

 sixth molar, the first three occupying but a tliird of the arch. 

 The relative density of the dentine and the convoluted enamel 

 differs greatly, so that the dentine is more rapidly worn and the 

 enamel stands in sharp ridges from the table of the teeth. 



Eruption of the Temporary Teeth, 

 incisors. 



Considerable diversity of description is found among the 

 older writers as to the time of eruption of the teeth in the sheep 

 from the fact that some studied them in the common races of 

 Central Europe, while others examined them only in the per- 

 fected races of England. At the present day the studies of the 

 latter will be found more accurate, as few flocks can be found 

 which are not well bred or mixed more or less with the finer 

 races. 



At birth, the lamb may have the pinchers and first inter- 

 mediate teeth through the gums, or the anterior borders of these 

 teeth may show a whitish line where they press against the gum, 

 which they pierce in from three to five days. The second in- 

 termediate emerges from the gum about the tenth day, and is 

 followed tardily by the corner teeth, which do not appear until 

 the twenty-eighth or thirtieth day. 



MOLARS. 



The three temporary molars in each arch appear about the 

 third week, when we find the first six incisors sufficiently ad- 

 vanced from the gums to allow the young animal to nip herbage, 

 which is to be ground by the larger teeth. 



Alterations during the First Year. 

 One to Three Months. — During this time there is little 

 change in the teeth. They are slightly more prominent, but 

 retain their virgin appearance. 



