666 THE PLEISTOCENE PERIOD 



the coast, arctic mollusks lived along the shore and were buried in 

 marine clays deposited while the eskers were being made. 1 The 

 same species live now in waters that are near the freezing point most 

 of the year. Remains of walruses, seals, and whales also have been 

 found. When an arm of the sea occupied the lower St. Lawrence 

 and Champlain valleys (p. 640), it was peopled by a marine fauna 

 similar to that which now lives about the mouth of the St. Lawrence 

 and on the coast of Labrador. 



On southerly coasts. Away from the immediate influences of 

 the ice-sheets, the record of marine life does not indicate any pro- 

 found departure from the progressive modernization that had been 

 in progress through the Tertiary period. It has been stated by Dall 

 that the Pleistocene fauna of the Atlantic coast does not imply as 

 cold waters as the Oligocene fauna does, and by Arnold that the 

 Pleistocene fauna of the California coast does not indicate a climate 

 as cool as that of the Pliocene. It is to be noted, however, that the 

 known marine record may not cover more than a small part of the 

 Pleistocene period, and it is not certain perhaps not probable 

 that the portion represented corresponds to any one of the glacial 

 epochs. When the ice was pushing into the ocean on the coast of 

 Maine, as in the late Wisconsin epoch, and an arctic fauna occupied 

 that coast, it is scarcely probable that a warm-temperate fauna 

 lived on the southern coast; nor is it probable that, when icebergs 

 were being discharged into Puget Sound, and along all the coast 

 farther north, a warm-temperate fauna lived on the California 

 coast; but warm- temperate faunas on those coasts during inter- 

 glacial epochs are entirely consistent with a climate such as that 

 suggested by the Don River beds. 



Terrestrial Life of N on- glaciated Regions 



The life of the lands far from the glaciated areas cannot now 

 be correlated closely with the glacial and interglacial stages. In 

 North America, northerly types such as the mammoth and mastodon, 

 the bear, bison, reindeer, and musk-ox, apparently driven south by 

 the advancing ice, were characteristic of these faunas. In the mid- 

 latitudes of North America there were several types on the verge of 

 extinction, such as the horse, tapir, llama, and saber-tooth cat. It 

 is not improbable that there was intermigration with Eurasia by 



1 Stone, Mon., U. S. Geol. Surv., XXXIV, 1899, pp. 53-54, and Bastin, Rock- 

 land, Me., folio, U. S. Geol. Surv. 



