542 GEOGRAPHICAL ZOOLOGY. [part iv. 



American Pliocene deposits being ancestral forms of Canidse 

 and Felidse. It seems probable, therefore, that the order had 

 attained a considerable development before it reached the 

 Western Hemisphere. The Procyonidse, now confined to 

 America, are not very ancient ; and the occurrence of a few 

 allied forms in the Himalayas {^lurus and ^^lurojms) render 

 it probable that their common ancestors entered North America 

 from the Palaearctic region during the Miocene period, but being 

 a rather low type they have succumbed under the competition of 

 higher forms in most parts of the Eastern Hemisphere. Bears 

 and Weasels are probably still more recent emigrants to 

 America. The aquatic carnivora (Seals, &c.) are, as might be 

 expected, more widely and uniformly distributed, but there is 

 little evidence to show at what period the type was first 

 developed. 



Ungulata. — These are the dominant vegetable-feeders of the 

 great continents, and they have steadily increased in numbers 

 and in . specialisation from the oldest Tertiary times- to the 

 present day. Being generally of larger size and less active 

 than the Carnivora, they have somewhat more restricted powers 

 of dispersal. We have good evidence that their wide range over 

 the globe is a comparatively recent phenomenon. Tapirs and 

 Llamas have probably not long inhabited South America, while 

 Ehinoceroses and Antqlopes were once, perhaps, unknown in 

 Africa, although abounding in Europe and Asia. Swine are 

 one of the most ancient types in both hemispheres ; and their 

 great hardiness, their omnivorous diet, and their powers of 

 swimming, have led to their wide distribution. The sheep and 

 goats, on the other hand, are perhaps the most recent develop- 

 ment of the Ungulata, and they seem to have arisen in the 

 Paliearctic region at a time when its climate already ap- 

 proximated to that which now prevails. Hence they are 

 pre-eminently a Temperate group, never found within the 

 Tropics except upon a few mountain ranges. 



Prdboscidca. — These huge animals (the Elephants and Masto- 

 dons) appear to have originated in the warmer parts of the 

 Palaiarctic region, but they soon spread over all the great 



