244 



THE WORLD OF LIFE 



same period in Europe, and less so in !N"orth America. As 

 shown in the restoration in Fig. 80, it somewhat resembled 

 the tapir; but other genera are more like horses, and show a 

 series of gradations in the feet towards those of the horse- 

 tribe, as shown bj Hnxley's figures reproduced in my Dar^vin- 



ism. 



The Origin of Elephants 



Till quite recently one of the unsolved problems of palaeon- 

 tology was how to explain the development of the Proboscidea 

 or elephant tribe from other hoofed animals. Hitherto extinct 

 species of these huge beasts had been found in a fossil state 

 as far back as the Miocene (or middle Tertiary) in various 

 parts of Europe, Asia, and Xorth America ; one species, the 

 mammoth, being found ice-preserved in Arctic Siberia in great 

 quantities. Some of these w^ere somewhat larger than existing 

 elephants, and several had enormously large or strangely curved 

 tusks; but, with the exception of Dinotherium, which had 

 the lower jaw and tusks bent downwards, and Tetrabelodon, 

 with elongated jaws and nearly straight tusks, none were very 

 different from the living types and gave no clue to their line 

 of descent. But less than ten years ago a number of fossils 

 have been obtained from the middle and higher Eocene beds 

 of the Fayoum district of Egypt, which give the long-hoped-for 

 missing link connecting the elephants with other ungulates. 



The most primi- 

 tive form now discov- 

 ered was about the 

 size of a very large 

 dog, and its skull 

 does not differ very 

 strikin2:lv from those 

 of other primitive 

 ungulates. It has, 

 Fig. 81. — Skull of Moeritherium lyonsi. however some slie'ht 

 From the Middle Eocene cf the Fayoum, Egypt. One- , . '. . , ^ , 



seventh nat. size. (B.M. Guide.) peculiarities whlch 



