8 OKIGIN OF LIFE IN AMERICA 



Asia to Europe, it became extinct in America as well as in 

 Greenland. 



Part of one section of the old musk ox stock returned to 

 North America by way of Asia, while another travelled by 

 means of a north Atlantic land connection to southern Green- 

 land, gradually finding its way along the eastern and western 

 coasts to northern Greenland. Meanwhile the musk ox had 

 entered Alaska again from Asia and crossed the Mackenzie 

 River into arctic Canada, where some of the peculiar forms 

 originated. 



Dr. Kowarzik promises us further contributions to this 

 interesting problem from a palaeontological point of view. 

 These will be of particular value in elucidating the question 

 of the relationship between the European and the Greenland 

 forms of the musk ox. I agree in so far with Dr. Kowarzik, 

 as I feel convinced .that the musk ox originated in North 

 America in pre-Glacial times, but I differ in most of his other 

 views. If land connections existed between North America 

 and Asia, and between North America and Europe, they must 

 have persisted through Pliocene to early Pleistocene times. 

 I am of opinion, .therefore, that the musk ox spread east- 

 ward to Europe and westward to Asia as long as land 

 bridges enabled it to do so. It is quite possible that the 

 Asiatic section subsequently travelled westward to Europe, 

 but neither of them succeeded in returning to their native 

 land. The musk oxen we find in Greenland and arctic 

 America probably survived the Ice Age where they now 

 live. This opinion has the support of Dr. F. Wright * and 

 Professor Upham as the result of their special study of the 

 geological history of Greenland. 



Not long ago the musk ox was still found in Alaska. Now 

 it has been quite exterminated west of the Mackenzie River. 

 As Dr. Allen remarks, the genus Ovibos is a declining type, 

 which has attained its last stronghold in the arctic barren 

 grounds. Wherever it is within the grasp of man it will 

 soon be a creature of the past. 



We possess no undoubted evidence of the existing species 

 of musk ox having ever penetrated as far south as the United 

 States, nevertheless it is quite possible that the fragmentary 

 * Wright, F. F., and Warren Upham, " Greenland Icefields," p. 332. 



