BARREN-GROUND CARIBOU. HI 



nally separated with no physical barrier between them. Accord- 

 ing to a universal law of selection the larger males of the wood- 

 land caribou would have driven off the males of the smaller 

 species, whenever they did meet on the common ground, and 

 would have left their impress upon their progeny, which being 

 larger and stronger than the pure bloods would soon have 

 usurped the entire paternity of the race and all distinction would 

 long since have been obliterated. It is no answer to this to refer 

 me to different varieties of the same species occupying different 

 and distant localities, and which vary in size, for instance, as 

 much as these do, as the Virginia deer or the mule deer. Tliose 

 species are not migratory, so that they remain substantially in the 

 same locality for many generations, if not driven away by vio- 

 lence, so that climate, aliment, and other accidental conditions 

 may in time produce a hereditary impress upon tliose occupying 

 the particular locality where the particular causes exist. This is 

 not possible with migratory animals, where as in this case noth- 

 ing but an imaginary line separates the territory occupied by 

 each, and where even that line is frequently if not annually over- 

 stepped by individuals. Even without the habit, mentioned by 

 Richardson, of the southern species migrating north and the north- 

 ern species south in the fall, the habit of migration would in time 

 have brought them together, when the larger males of the south 

 would have become the progenitors of the entire race, and the 

 broad distinctions, now so conspicuous and so constant, would 

 have been lost. If not migratory, then we might accept the 

 explanation suggested by their different localities as a sufficient 

 reason for the differences observed. 



Why, then, do these two members of this great family live 

 upon contiguous and even overlapping territories and continue so 

 completely separated, with no visible cause to keep them apart ? 

 It must be because of inherent constitutional, specific differences. 

 It is evident that their well-beings require different conditions of 

 life arising from organic differences which are permanent and in- 

 flexible : one cannot live and prosper where the other must live 

 in order to prosper. 



We learn of the differences which have been pointed out, as it 

 were, by accident, for their habitat is so remote and inaccessible 

 that the Barren-ground Caribous have been rarely visited by com- 

 petent naturalists, and I have no doubt that when they shall be 

 carefully studied and thoroughly understood by competent ob- 

 servers, still broader distinctions between the two species will be 



