. Bulletin of the Southern California Academy of Sciences. Science; Natural history; Natural history -- California. Skull of young Camel. middle Oligocene called Proebrotherium, which in turn was preceeded in the lower or Unita Oligocene by a representative called Lepto tragulus, which itself may have sprung from a still earlier form, the Homacodon of the Bridger (earlier Eocene) beds. It is quite evident that the camels of today came in rather direct line from more generalized forms and were originally a North Ameri- can group. Hence when the camel lay down and died in the Brea Beds, it was b
. Bulletin of the Southern California Academy of Sciences. Science; Natural history; Natural history -- California. Skull of young Camel. middle Oligocene called Proebrotherium, which in turn was preceeded in the lower or Unita Oligocene by a representative called Lepto tragulus, which itself may have sprung from a still earlier form, the Homacodon of the Bridger (earlier Eocene) beds. It is quite evident that the camels of today came in rather direct line from more generalized forms and were originally a North Ameri- can group. Hence when the camel lay down and died in the Brea Beds, it was buried in its native country. From this favored spot the earliest forms began their long process of differentiation and migration of the earth. That the molar dentition of the Siwalik camels is very similar to that of the vicunas and guanacos of South America is remarkable, and a common branch must appear somewhere in the genetic tree. Why this species (having peculiar molar teeth) should become extinct in India, but develop and survive in South America, is likewise a problem. What native tendency or habit or climatic conditions or character of food should, in two such widely separated regions, give rise to the dentition, and in the one fade away, and in the other survive, are queries that remain unanswered. In fact, the disappearance of the camels from North America is very strange indeed, yet not more singular and perplexing than the disappearance of this whole great group of other large animals repre- sented in the Brea Beds. On the whole then, we have here a very remarkable illustration of world-wide migration, beginning in the United States in the lower Eocene (Fintocene Oligocene) beds. From here the distribution was rapid over the Mississippi valley with one branch, (llamas) turning southward, and probably by the way of tne Isthmus of Panama, entered the South American continent in the Post-pleistocene times, to be spread over the whole region and subsequently to survive
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