398 A MANUAL OF DENTAL ANATOMY. 



rooted, a thing anomalous either in an incisor or a canine, 

 though found in the canine of Gymnura, which is beyond 

 question in the maxillary bone. 



Next come three minute premolars, and a fourth, which 

 is much larger than the others : these all have single crowns, 

 consisting of little more than a single sharply-pointed cusp. 



The first two upper molars are large teeth bristling with 

 cusps : the third is much reduced in size and simplified 



j- Aw I; Sice 



in pattern. In the lower jaw the four front teeth arc all 

 small, but the fourth or outermost of these incisors is called 

 by some writers the lower canine, because, when the teeth 

 are closed, it passes in front of the upper caniniform tooth. 



Nevertheless the tooth which does the work of a canine in 

 the lower jaw is the fifth counting from the front : this is a 

 two-rooted tooth, and conforms so closely with the three 

 teeth behind it in configuration, that it is obviously only one 

 of these premolars developed to a greater length than the 

 others. It closes behind the caniniform upper tooth, so 

 cannot on this ground be called a canine by those who 

 attach importance to the term. 



( ! ) Upper and lower teeth of the common Mole. The functionless milk 

 teeth (after Spence Bate) are placed above the permanent teeth which dis- 

 place them. 



