The Proboscldea — Mastodon. 13 



the lower jaw ; and always one pair, and sometimes two pairs, 

 of tusks were present in the adult animal (see Figs. 14 and 26). 

 These tusks, like the front teeth of th? rat and the rabbit, were 

 provided with persistent pulp-cavities, and continued to grow 

 as long- as the animal lived. In one species, Mastodon anqusti- 

 dens, they were partly coated with enamel. They had also 



Mastodon. 

 Pier-cases, 

 Nos. 37 and 

 38. 



Table-case, 

 No. 23. , 



Fig. 13. — The fourth left upper milk-molar of Mastodon aroi mentis (.Croizet et Jobert) : 

 from :he Norwich Crag, Postwick, Norfolk. 



Fio. 14. — Skull and lower Jaw of Mastodon longirostris Mvaurj) ; showing tusks in both upper 

 and lower Jaw, from the Upper Miocene, Eppelsiieim, Germany. (See Pier-case 37.) 



three deciduous or milk-molars, and in some species, two pre- 

 molars, on each side, both in the upper and lower jaws, and 



