Straits : a migration from the Ganges over the Himalayas and the high 

 plateaus of Thibet into Mongolia would seem to present insuperable diffi- 

 culties. The supposition of casual wanderings of any individuals, or tribes, 

 of the Sanscrit-speaking Aryans of the Ganges, through China to Behr-. 

 ing's Straits, or by the driftings of boats across the Pacific from the coasts 

 of Asia to Central America or Mexico, within the period of the Aryan 

 occupation of the banks of that river, would seem to be equally impracti- 

 cable ; though such driftings from the coasts of Eastern Asia have un- 

 doubtedly taken place at different periods. The language, thus carried, 

 would be Malayan, or Chinese, or Japanese, and not Aryan, though it 

 would be still possible, perhaps, that some few words of Sanscrit origin 

 might have been mixed with some language of the eastern coasts. This 

 theory might explain the presence of some few Sanscrit words in the 

 Nahuatl of Mexico, without reaching back at all to the first origin of the 

 Mexican peoples, or to the first migration of the Nahuatl-speaking tribes 

 into Mexico. 



The traditions of the Aztecs to the effect that they came to Mexico from 

 the north are too recent to throw any light on their actual origin; and they 

 are sufficiently explained by the local migrations of the constantly wan- 

 dering American tribes in times shortly preceding the Spanish conquest, 

 and. if true, they do not require us to suppose a migration from apy place 

 farther north than the valley of the Gila river, where very ancient remains 

 of human habitation have been found ; besides, that the recent researches 

 of Bancroft and others would rather indicate that the Nahualt- speaking 

 Mexicans really came into Mexico from the direction of Central America. 

 Seiior Mendoza places the time of the supposed migration of his San- 

 scrit-speaking progenitors of the Nahuatl people in the early stages of the 

 Quaternary epoch. Before this epoch, the land connection between the 

 two continents at Behring's Straits had been cut off by the sinking of the 

 land ; and the supposed route of migration, either from the banks of the 

 Ganges, or from the basin of the Caspian Sea, for such Sanscrit-speaking 

 progenitors, by this northern circuit, and through the regions of intense 

 cold, and within any period that can be allowable for the antiquity of the 

 Aryan speech at all, would seem to be inadmissible in the present state of 

 our knowledge. 



Then as to the other hypothesis of a tropical land connection of the 

 continents, geological considerations preclude the supposition of such a 

 land connection since the Miocene-Tertiary jDcriod, and certainly within 

 any period than can be allowed for the antiquity of the Aryan language. 

 But as late as the Pliocene period (as Mr. Wallace and Prof. Marsh have 

 noticed) there was a land connection across Behring's Straits, when cli- 

 mates were warm even in that high latitude ; and there was then, in all 

 probability, a further extension eastward of the shores of the Asiatic con- 

 tinent, affording an easy passage along the coasts of Asia from the Malayan 

 peninsula by continuous land in the direction of Japan and the Aleutian 

 Islands to North America. And there can be little room for doubt, now. 



