90 NATURAL HISTORY OP 



in latitudes where they endure a winter state of tor- 

 pidity beneath ice, as an evidence that the great Sau- 

 rians in that region have not yet entirely worked out 

 their mission ; whereas, on the old continent, they had 

 ceased to exist in high latitudes, long before the extinc- 

 tion of the great Ungulata. The vast extent of sandy 

 alluvial territory, from the Gulf of Mexico to the sum- 

 mit of Long Island, appears as if it were a late deposit, 

 in part debris of the Mexican and Carribbean portions 

 of the continent, carried north, and thrown off when 

 the gulf stream was formed. At the mouth of the 

 Mississippi, the sea, of small depth along the whole 

 coast, continues to recede before the delta of the river ; 

 and the Florida and Carolina shores northward, form 

 a series of lagoons on the ocean side. The stream 

 rushes onwards in a north-east direction, and with a 

 gradually decreasing velocity and temperature (though 

 both are still very perceptible off New York), until it 

 is finally neutralized at Nantucket, and the last particles 

 of deposit suspended in it are precipitated to form the 

 banks of Newfoundland. A continent torn asunder and 

 washed away, alone could furnish the immense alluvial 

 surface and submarine banks here noticed. The rivers 

 of the United States and Canada, are not of a nature to 

 have added more than feeble deltas, such as that of the 

 Hudson at Sandyhook. Great changes are commemo- 

 rated by the Indians in their mythological and legen- 

 dary tales, both in the direction of the tides and in 

 ancient accumulations of ice. * 



* See Appendix. 



