354 



PALAEONTOLOGY 



or five ridges* For the Mastodons with penultimate and 

 antepenultimate grinders with three ridges, Dr. Falconer pro- 



poses the name Triloplwdon. In the Mastodon Ohioticus the 

 lower jaw lias two tusks in the young of both sexes ; these 



* Owen's " Odontogvnphy," ItO, 18t. r >, p. 617. pi. 144. 



