236 COMPLEX AND COMPOUND TEETH. 



batrachians, which T have called " Labyrinthoclonts,"^ ex- 

 hibit, as the name implies, a remarkable instance of this 

 kind of complexit}^. The tooth appears to be of the 

 simple conical kind, with the exterior surface merely 

 striated longitudinally ; but, on making a transverse sec- 

 tion, as in Fig. 56, each streak is a fissure into which the 

 very thin external layer of cement, c, is reflected into the 

 body of the tooth, following the sinuous wavings of the 

 lobes of dentine, c/, which diverge from the central pulp 

 cavity, a. The inflected fold of cement, c, runs straight 



TRANSVERSE SECTION OF TOOTH OF LABYRINTHODOX. 



for about half a line, and then becomes wavy, the waves 

 rapidly increasing in breadth as they recede from the 

 periphery of the tooth ; the first two, three, or four un- 

 dulations are simple, then their contour itself becomes 

 broken by smaller or secondary waves; these become 

 stronger as the fold approaches the centre of the tooth, 



• "Proceedings of the Geological Society," Jan. 20, 1841, p. 257. 



