EVOLUTION OF CAMELS 
than a jack rabbit, and of course very uncamel-like in general aspect. It 
had, for instance, four distinct and equally important toes, protected by 
hoofs, on the fore feet (but only two toes reached the ground on the hind 
feet), and the metapodials were entirely separate. The teeth were ‘“‘buno- 
dont,” that is, their crowns were formed by a pavementlike arrangement 
of rounded tubercles, as in modern pigs, fit only for crushing soft food; 
short canines and upper incisors were present, and there was no diastema. 
The skeleton of these early forms is more llamalike than cameloid. The 
next advanced form is greater in size, and the lateral toes are no longer 
useful, but hang to the side of the foot above the ground like a deer’s. In 
the next, from the lower part of the White River Miocene deposits of 
Wyoming, the size has increased to that of a coyote. Then follow a series 
of improvements on lines parallel with the evolution of the early horses, 
size increasing, the teeth becoming more suitable to grazing uses, the 
metapodials tending more and more to solidify, and the external appear- 
ance gradually approximating modern examples of the tribe. 
At the close of the Miocene, a dispersion of the race began. Changes 
took place in geographical and climatic conditions which made the plateau 
of the western United States unfavorable for them. One branch migrated 
somehow into the Old World, and finding a suitable country in Africa and 
southern Asia, persisted and developed there into the two existing species 
— the single-humped Arabian and the double-humped Bactrian. Another 
side branch made its way into South America and found a congenial home 
upon its open southern plains, where it developed into the somewhat sheep- 
like huanaco and vicunia. Here there was firmer, stonier ground, less 
need for the great sustaining pad beneath the foot, and more need for speed; 
hence these South American forms show smaller pads and the nails are 
more hooflike. This gives us the explanation of the odd present geo- 
graphical distribution of the camel family. 
Nevertheless, the total extinction of North American camels was ex- 
tremely slow, and allowed time for the development of local forms all 
through the Pliocene and Pleistocene, or closing epochs of the Tertiary 
era. One of these was a queer, aberrant form a third larger than the mod- 
ern dromedary, which must have towered up like a giraffe as it grazed upon 
our western plains of those days. Another, that lived near the close of 
Pleistocene times, was so like the true camels of our day that Dr. Wortman 
believes it may have been their ancestor. 
The camels, then, have always been creatures of the world’s 
desert places, and all their extraordinary peculiarities, outward 
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