THE TEETH OF MAMMALS. 303 



of allied creatures will enable us to decide whether a,,parti- 

 cular tooth is to be referred to the milk or to the permanent 

 series ; as occasionally teeth of the latter set are cut very 

 early, at a time when the milk teeth are all in place, and 

 are shed during adult life. Professor Flower gives as an 

 example of this, the first premolar of the hippopotamus. 



CUVIER. Dents des Mammiferes. 



DE BLAINVILLE. Osteographie. 18391864. 



OWEN. Odontography. 1845. 



GIEBEL. Odontographie. 1855. 



FLOWER. Lectures on Odontology (British Med. Journal, 1871). 



