ON REINDEER 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 (Rangifer) 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. II., “ Scaphoceros tyrelli,” p. 178. 
