XIII 



OF ELEPHANTS' TEETH 



901 



These columns soon fuse and vanish as the cusps wear down; and 

 each denticule now appears as a continuous ring of enamel, within 



Fig. 441, 



b c 



Abnormal incisor teeth: a, b, of rabbit; c, of beaver. 

 After Mcintosh. 



which the dentine is exposed and around which the cement accumu- 

 lates*. A single great molar is made up of nearly a dozen of these 



Fig. 442. A dental unit, or element of the composite molar tooth, of an Indian 

 elephant. It consists of five "columns", terminating in yet unworn "cusps". 



* See Blair's Osteographia elephantma, 1713, Tab. ni, 19; also the figures in 

 F. van Gaver's :6tude de la tete d'un jeune Elephant d'Asie, Ann. Mus. Marseille, 

 XX, 1925, Cf. also L. Bolk, Zur Ontogenie des Elefantengebisses, Odontologische 

 Studien, ni, Leipzig, 1919. 



