COMPARATIVE ANATOMY OF THE TEETH. 27 T 



either side instead of four, as in man and the higher 

 monkey. 



The two incisors of the upper jaw are separated by a 

 wide space from the two on the left, and are small, vertical, 

 and have their crowns short and expanded. 



The canine is long, compressed, and curved, with its 

 edge sharp and pointed. The three bicuspids present, on 

 the inner side of their crowns, a tubercle, while on their 

 outer there is extended a compressed and pointed lobe. 



Both jaws have their first true molars the largest. The 

 first bicuspid, in the upper jaw, has its two roots connate 

 or joined together; those of the other two are distinct. 

 The roots of the upper molars, as in the human teeth, are 

 three in number ; but in the lower jaw, both bicuspids and 

 molars have only two roots. The number of deciduous 

 teeth in the lemurs is twenty-four, instead of twenty, as in 

 man the excess being in the molars. Among the quad- 

 rumana there are two genera described, which are most 

 remarkable for their very singular and anomalous denti- 

 tion. They consist of the goleopitliecus (the weasel-like 

 monkey) and the cheiromys. 



The former are said to resemble the bat, in having a 

 kind of wing, formed of a fold of the integument,, reaching 

 from the front to the hind extremity, and may be called 

 flying monkeys. 



The teeth in this genus are thirty-four in number, i. e. 

 four incisors in the upper jaw, two on either side, and six 

 in the lower jaw, three on either side, making ten incisors 

 in all two more than in man. The two anterior upper 

 incisors have a wide space between them, are very small, 

 and have their crowns expanded and presenting three or 

 four tubercles. The second incisor of the upper jaw, which 

 is said to be connected with the intermaxillary bone, has 

 one very striking peculiarity in having two roots. Its 

 crown is of a triangular shape, having, at the front and 

 posterior base, a small talon also dentations, two anterior 

 and three posterior, at the same points. 



The upper canine has, very unlike the human, two roots. 



