ON EEINDEEE AND CLIMATE 155 



succeeded in adapting itself to an arctic habitat. The avail- 

 able evidence is all in favour of a gradual advance having 

 taken place of those large sheep-like forms from a more 

 southern to a northern habitat during late Tertiary times. 

 Mr. Osgood* has now discovered another extinct relation of 

 the musk ox in the Yukon Territory of north-western Canada. 

 He first described it as Scaphoceros tyrelli (including Ovibos 

 cavifrons of Leidy in the same new genus), and suggested 

 that Scaphoceros may be ancestral to Ovibos. According to 

 Mr. Barnum Brown, the name Symbos has now been substi- 

 tuted for Scaphoceros. Hence Symbos is known from Indian 

 Territory, Iowa, Missouri, Ohio, Pennsylvania, Kansas, 

 Arkansas, from Yukon Territory and from Alaska. Yet even 

 its former presence in Alaska cannot stamp Symbos as a cold- 

 loving animal, for close to its remains were dug up those of 

 a Mastodon, and who would be prepared to argue that the 

 Mastodon is an indicator of a cold climate ? 



Lastly, Dr. Hay claims that the reindeer (Rangif er) having 

 occurred so far south of its present habitat (Fig. 10) in 

 Pleistocene times is a proof of the existence of a cold climate 

 at that time in the United States. I have discussed this pro- 

 blem once before (pp. 3 — 6), but I may add a few remarks. 

 If the drift area of North. America had been covered largely by 

 the sea, as I believe it was, during part of the Glacial Epoch, 

 the country which was still habitable for the reindeer must 

 have been greatly reduced. Hence a southward emigration 

 was the only possible chance of survival for some herds of 

 reindeer. Driven out of their home by the stress of circum- 

 stances, they would have passed into a district, even if the 

 latter had been unsuitable to their requirements. At any rate, 

 we know that reindeer can live perfectly well in a temperate 

 climate and that they still inhabited Scotland in the twelfth 

 century long after the Glacial Epoch had passed away. I 

 cannot therefore consider its former presence in the United 

 States a proof of a cold climate. That it could only have 

 penetrated south in small numbers is indicated by its 

 total absence from all the North American caves hitherto 

 examined except one, and from almost all the other Pleisto- 



* Osgood, W. H., " Scaphoceros tyrelli," p. 178. 



