TEETH. 



871 



denticles, as in the Gafeopithecus, blending long diameter of the tooth. When the tooth 

 together into a common base in the fully-de- is bisected vertically and lengthwise, the three 

 veloped tooth. substances, d dentine, e enamel, and c cement, 



Fig. 557. 



Section of lower incisor of Galeopiihecus 

 (Magnified.) 



Section of molar of Elephant. 



are seen interblended as in Jig. 557 , in which 

 p is the common pulp-cavity, and r one of 

 the roots of this complex tooth. 



A still more complex, grinding apparatus is 

 found in certain fishes. The lower pharyngeal 



A figure is given of the grinding surface of bone of the parrot-fish (Scams*), for ex- 

 the third true molar of the Phacochcerus Pal- ample, supports a dental plate with a tri- 



Fig. 558. 



Two of (he upper pharyngeal teeth, Scarus. (Magnified.) 



fasii, in PI. HO, Jig. 4, of my " Odontography." turating surface like that of the compound 

 In the elephant the denticles of the com- molars of the Phacochcerus. The interlocked 

 pound molars are in the form of plates, vertical upper pharyngeals (Jig. 565.) support dental 

 to the grinding surface and tranverse to the * Odontography, pi. 51., fig. 3. 



3 K 4 



