142 



The North American Cervidce. 



BARREN-GROUND CARIBOU. 



on their inferior surfaces. When the animal trots swiftly, these dew- 

 claws strike against one another with a loud, clattering noise. 



The food of this species consists principally of the so-called rein- 

 deer moss ( Cladonia rangiferina), which, in winter, they reach 

 by scraping away the snow with their hoofs ; but they also eat 

 other mosses and lichens which grow upon the trees or on the 

 barrens which they frequent. During the summer they feed on 

 grasses and the tender shoots of shrubs, but do not appear at 

 any season to strip the saplings of their bark as do the moose. 

 The young are brought forth in May. 



As to the habits of the barren-ground caribou we are not 

 well informed, for the species is known only to arctic explorers 

 and to the servants of the Hudson Bay Company, in British 

 America. Richardson's accounts of it are, however, quite full, and 

 from these it appears that this form does not differ materially 

 from its woodland relative, except in the range of country which it 

 inhabits, and in the greater extent and regularitv of its migrations. 

 The woodland caribou is much more southern in habitat, and fre- 

 quents especially the forests of British America, occurring regularly 

 in Maine and perhaps in the Rocky Mountain region of the United 

 States along the border. The barren -ground deer, on the other 

 hand, occupies the wide treeless plains about the Arctic Sea, where 



