322 THE SKELETON OF THE RABBIT. 



of the upper jaw, lodged in alveoli in the pre- 

 maxillse. 



a. The anterior incisors are long, and curved 

 almost into semicircles, the greater part of 

 each being lodged in an alveolus which 

 extends almost to the hinder end of the 

 bone. Along the anterior surface the 

 enamel is thick, and folded so as to form 

 a longitudinal groove. Behind and at the 

 side it is much thinner, and hence wears 

 away sooner, rendering the cutting edge 

 chisel-shaped. 



y8. The posterior incisors, which are lodged in 

 alveoli immediately behind the anterior 

 ones, are much smaller and slightly curved. 



ii. The grinding teeth form a set of six teeth on 

 each side, borne by the maxilla, and fall into 

 two groups. 



a. The premolars are the three anterior grinders 

 of each side, and are distinguished from 

 the posterior ones by the fact that, like the 

 incisors, they are preceded in early life by 

 ' milk ' or deciduous teeth, which in the 

 rabbit are shed shortly after birth. 



Each premolar is flattened from before 

 backwards, and each of the two hinder 

 ones has a deep groove along its outer 

 surface which carries the enamel almost 

 across the tooth, giving rise to a promi- 

 nent ridge on the grinding surface. b 



(3. The molars are the three posterior grinders on 

 each side : they differ from the premolars, 

 in having no deciduous predecessors. The 

 first two are similar to the premolars ; the 

 last is small and not grooved. 



