302 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1923 



the Canadian Government and came from Banff, Alberta. Several 

 young have been born in the park. 



THE MUSK OX 



Specimens of the Greenland musk ox (Ovibos moschatus icardi) 

 were first received at the National Zoological Park in 1922. The 

 musk ox is now found only in the barren Canadian Arctic and in 

 Greenland, but, as shown by its fossil and sub-fossil remains, it 

 formerly inhabited Alaska and northern Europe and Asia. Its 

 range has been greatly restricted within historic times, great num- 

 bers of the animals having been killed by explorers of the North. 

 Present-day protection by the Canadian and Danish Governments 

 will doubtless save the species from actual extermination, and plans 

 are even being made to attempt the semidomestication of some of 

 the remaining herds* for commercial purposes. Owing to the nature 

 of the animal its protection should not be difficult, and it should 

 prove a valuable addition to the domestic animals of the northern 

 treeless wastes. The musk ox is usually considered the only repre- 

 sentative of a special subfamily of bovine animals. 



BISON, YAK, AND THEIB ALLIES 



The herd of American bison (Bison bison) maintained in the 

 National Zoological Park has been brought together from various 

 sources. It is now kept at approximately 17 head, and the surplus 

 stock is exchanged to other parks and bison reservations. There are 

 now many places where bison herds are kept and carefully protected 

 and bred so that all danger of the extinction of this famous Ameri- 

 can ruminant is past. The number of animals is increasing yearly 

 under the direction of the American and Canadian Governments 

 and the American Bison Society; new herds and reservations to 

 accommodate the surplus animals have been created. 



The yak (Poephagus grunniens) is found in a wild state in the 

 very high mountains of central Asia, in Ladak, Tibet, and Kan-su, 

 where it lives at altitudes varying from 14,000 to 20,000 feet. The 

 color of the wild stock is a blackish brown. Tame, semiwild, and 

 feral herds ranging northward into the Altai Mountains at much 

 lower altitudes, even to the Siberian slopes of the Little Altai, are 

 of mixed colors, black, brown, gray, and white. Both sexes nor- 

 mally have horns; those of the male ofttimes are of great length. 

 The natives of central Asia say that the yak is not successfully 

 kept below 4,000 feet in that region. The animals in the Zoological 

 Park, at what is practically sea level, do not seem to suffer from the 

 low altitude, and frequently breed. 



