MIGRATIONS 75 



Labrador species. Perhaps what is now Newfoundland was 

 then the great winter resort for immense herds. One cannot 

 say for certain, because the weather conditions which prevailed 

 in those days are not known with absolute certainty. The 

 past is wrapped in so much mystery, and our theories con- 

 tinue to change as we investigate more carefully ; what 

 to-day seems a certainty is to-morrow thrown aside for 

 newer and more advanced ideas, and we never know what 

 is the final decision. Such being the case, we must be 

 satisfied to study the migration chiefly by existing conditions, 

 and for lack of a better reason we are practically forced to 

 the conclusion that the search for food is the cause of the 

 southerly migration. But what about the return journey ? 

 Why should the animals go back to the north ? So far as 

 we can judge from appearances, the conditions in various 

 parts of the island do not show any great differences during 

 the summer ; the food in the more southerly parts is 

 about the same as in the north, it is certainly abundant, and 

 there is no doubt that it is what the Caribou want, for other- 

 wise so many of them would not remain scattered over the 

 country which is abandoned by the northern herds when 

 winter has passed. The theory advanced by some writers 

 that flies play an important part in the cause of migration is 

 I believe utterly without foundation, because the black fly 

 is found in practically every part of the island during the 

 summer months, and the northern peninsula has its full 

 share of these pests. Even on the highest ridges, rocky and 

 with only the scantiest vegetation, miles away from the 

 forests, the black flies have been so numerous that they 

 made life miserable, so that when the migratory herds leave 

 the south they do not escape the warm weather pests. In 

 the very few places where the black flies are scarce, there are 

 but a few scattered Caribou during the summer. 



