CLASSIFICATION AND DISTRIBUTION OF ANIMALS. 355 



Riimmcintia. Recent Camelidce are only found in the Neotropical 

 and Palaearctic regions, but numerous forms occur in the Miocene 

 and later deposits of N. America, where the group originated. 



Tragulidce or mouse-deer have also a discontinuous area of 

 distribution W. Africa (Hyomoschus) and Oriental region 

 (Tragulus). This is accounted for by the presence of Miocene 

 forms in Europe, whence the family extended south. 



Deer occur in all the regions except the Ethiopian, but do not 

 extend far into the Australian region. They appear to have 

 taken origin in the Old World, from whence they reached 

 N. America in Miocene times, and afterwards passed to S. 

 America. 



Giraffes are at the present time confined to the Ethiopian 

 region, but fossil forms are known from S. Europe and India, 

 and a northern temperate origin is probable. 



Bovidce (oxen, sheep, antelopes, &c.) are present in all the regions 

 except the Neotropical, though they only just pass into the 

 Australian, and are scarce in the Nearctic. The family appears 

 to have originated in the Palsearctic and Oriental regions during 

 Miocene times. 



(b) Perissodactyla. Tapirs present a striking example of dis- 

 continuous distribution, being found, on the one hand, in the 

 Malay peninsula, Sumatra, and Borneo, and on the other, in S. 

 and Central America. True tapirs occur in the W. of Europe as 

 far back as Miocene times, but in America are not found further 

 back than the Pleistocene. Migration from the Palsearctic region 

 is thus indicated. 



Rhinoceroses are now only Ethiopian and Oriental, but they 

 appear to have originated in the Palsearctic region, whece they 

 extend back to the Miocene period. In Pliocene times they also 

 ranged into N. America. 



The genus Equus (horse, ass, zebra) is now limited to the 

 Ethiopian and Palsearctic regions. It appears to have originated 

 in the latter area during Miocene times, and then migrated not 

 only into the Ethiopian, but also into the Oriental, Nearctic, and 

 Neotropical regions, as proved by fossil forms. 



5. Sirenia. Manatus (manatee), E. coast of S. America, and 

 W. coast of Africa. Halicore (dugong), shores of Indian Ocean 

 and Red Sea. 



6. Bodentia. Ver}' widely distributed; occurring in all the 



