No. 646] THE FOSSIL PROBOSCIDEANS 455 



These animals wandered all over Europe, 

 Asia, and western N-orth America, 

 ly. ELEPHA^^^TOIDEA (the Elephant stock) 



9. Stegodontinae, the original members of which were 

 doubtless ancestral to all the higher elephants, 



Pleistocene of eastern Asia. ' ' ^ . * 



of the elephants beginning with varieties of the 

 Loxodon antiquus of the Upper Pliocene, which 

 wandered all over southern Eurasia and radiated 

 widely over Africa. 



11. Mammontinje, including (a) the Southern Mam- 



moths (Elephas planifrons of India and E. 

 meridionalis of Europe), from which is derived 

 E. imperator of North America, and (fc) the 

 Northern Mammoths, which probably include E. 

 column and the widespread E. primigenius of 



12. Elephantina?, the ^true' elephants (e. indicus of 



Pleistocene; pentadactyl pes. 



This twelve-fold branching of the proboscideans is 

 similar to the adaptive radiation which the author has 

 traced in the evolution of the horses, of the rhinoceroses, 

 and of the titanotheres, carrying the fundamental lines 

 of separation back to the Middle Miocene as the most 

 recent date, and to the Middle or Lower Eocene as the 

 most remote date. It will be observed from the diagram 

 (Fig. 1) that the shaded areas represent those probos- 

 cidean phyla of which remains have been discovered. 

 The large luisliadod area includes the entire Oligocene, 

 Mioceiif, and Lower and Middle Pliocene history of the 

 Elei)hantidiv which is still unknown but which is likely 

 to be revealed at any tim*' by discoveries liotli in Africa 

 and in central Asia. A very striking fact is that the 

 early member of the J':;h'i)hantoi(he. tlie Eh plms phn/i- 

 frons of the Upper Pliocene of India and the apparent 

 ancestor of the mammoths, is now antedated in geologic 

 time and in its transitional structure by the Elephas 

 aurora {i.e., of the rising sun region) of Japan. 



