82 COMPAEATIVE DENTAL ANATOMY 



mals are divided into two classes in reference to 

 the possession of one or two sets: those having 

 but one set are called Monophyodont, those giv- 



FiG. 29. — Teeth of human. Diphyodont and heterodont. 



ing rise to two sets are called Diphyodont. The 

 monophyodont mammals produce but one set, 

 which persists through life, — as some Armadillos, 

 Sloths, Cetacea, the common Eat, and others. 



