22 



TRANSACTIONS OF THE 



[not. 10, 



a few months old, and is shed at about the end of the second 

 year. The second, with eight plates, is worn for eight or nine 

 years. 



Incisors. 

 1—1 



Tablt of Dental Formulae. 

 Elephas primigenius, 

 Elephas Indicus, 

 Elephas Africanits, 

 Mastodon, 



Dinotherium, 



0-0 

 1—1 

 0—0 

 1—1 

 0-0 

 1—1 

 -1, or 0-0 



0-0 CO 

 1—1 



Canines. 

 0—0 



0-0 



0-0 



0-0 



0-0 



0-0 



0-0 

 0-0 

 0-0 

 0-0 



Premolars. Molars. 



6-6 



6-6 

 6—6 



6-6 



6—6 

 6—6 



6-6 



=26 



=26 



=26 



=26 or 38 



2—2 

 2—2 



Table of Ridges or Plates in the Molars. — 



Elephas primigenius, 

 Elephas Indicus, 

 Elephas Africanus, 

 Mastodon, 



First 

 Molar. 



4 

 4 

 3 



Second Third 



Molar. Molar. 



8 12 



8 12 



6 7 



Fourth 

 Molar. 



12 or 14 

 12 



7 



3-3 

 3—3 



Fifth 

 Molar. 



16 or 18 

 16 



Sixth 

 Molar. 



24 

 24 

 11 



Never over five. 



Skull. — Large, cellular, empty spaces or air-cells, highly 

 specialized ; brain cavity small. 



Brain. — Cerebrum large, highly convoluted ; cerebellum 

 much exposed. 



Skeleton. — Dorsal region of vertebral column long; only 

 three lumbar vertebrae ; four sacral vertebrae ; the centra flat- 

 ened; neck short; knee-joint low, giving the impression of the 

 joints bending in the wrong direction. 



Growth and Size. — The new-born are about three feet high. 

 They nurse nearly two years, become four feet high in the 



