356 



UNITED STATES. 



then fly away to their more northerly summer resi- 

 dence. 



Although these docks migrate in this manner j 

 there are very few places in which they are found. 

 It is not known that they frequent the waters north 

 of Chesapeake bay ; though it has been afHrmed that 

 a straggler has been now and then killed. Indeed, 

 their range to the southward is so circumscribed, 

 that they are rarely or never seen at present any 

 where but on the waters of the Susquehannah, and 

 the Potowmack and in vain do the sportsmen seek 

 them in the rivers of the southern states. Sometimes 

 they have been seen on the tables of the luxurious in 

 the city of New York ; but in these cases they have 

 always been sent from the Chesapeake. Formerly 

 they were frequent in James river, in Virginia, but 

 latterly they have deserted it altogether* This 

 abandonment of a plac^ formerly resorted to by 

 them, is supposed to be owing to a failure of the par- 

 ticular food which formerly invited them there. 



This food is of the vegetable kind ; for it would 

 scarcely be expected that a bird of such a delicate 

 taste at the table^, should subsist on animal aliment.. 

 They feed upon the roots of a coarse long grass which 

 grows in the two before-mentioned rivers, higher 

 toward their sources thaa the salt water extends. 

 And these roots which are large, succulent, and re- 

 semble in some respects those of celeri, are pro- 

 cured by diving; for the canvass back is a diver. 



Within the remembrance of people now alive, 

 canvass backs were so numerous on those parts of 



They, certaijily have been seen in Georgia, 



