Ill 



alluvion from the overflowing of those rivers, we might 

 reasonably expect, since it is well known, that in 

 every spring and autumnal flood, from time immemorial, 

 a great quantity of logs and drift wood is floated down 

 their currents, and carried into the sea, or deposited 

 in their beds, that we should find, particularly in the 

 banks of rivers, some of their remains deposited in 

 every foot of the alluvial formation, from the bed of the 

 rivers to the highest point that is inundated : but this 

 I believe is not the case. I have been zealous in my 

 endeavours to obtain information on this point ; and in 

 no one instance can I find, from the state of Maine to 

 the Mississippi, that vegetable remains have been dis- 

 covered between two or three feet below the surface, 

 and about the medium depth of forty feet ; except in 

 some swamps, where stumps and logs are sometimes 

 found at the depth of four or five feet, buried, in the 

 course of time, probably, by the decomposition of vege- 

 table matter : and also in alluvial islands in the channels 

 of rivers, where every foot of their depth, particularly 

 of that part which receives the force of the current, dis- 

 covers logs, brush- wood, bark, nuts, and leaves, pro- 

 miscuously thrown together and buried by successive 

 deposits of alluvion. 



3dly. In the great alluvial district of which I 

 have been speaking, and which contains, beneath its 

 surface, almost from one end to the other, an immense 

 and highly interesting cabinet of natural history, there 

 are found, besides deposites of vegetable substances, 

 great quantities of fossil remains, of fishes of various 



