92 On the Migration of North American Birds. 



are often met at sea during the period of their migration and are fre- 

 quently known to ahght on the rigging of vessels, where they rest, 

 for an hour or two, and then again pursue their onward course. 

 The other path of migration and probably the most common, to 

 which I refer, is along the Alleghany mountains which extend through 

 the whole interior of our country. They vary occasionally in their 

 flight so as to follow not only the range of mountains, but the cours- 

 es of rivers. In these views I am supported by Audubon and Nut- 

 tall, and they are strengthened by the fact that the Rose-breasted 

 Grosbeak, the Baltimore Oriole, the Scarlet Tanager and a number 

 of species of warblers that seldom visit the maritime districts of 

 Carolina are found to pass along our mountains and from thence 

 through the states of Louisiana, Mississippi, and Arkansas. Some of 

 these birds remain in Mexico ; some enter within the Tropics, and 

 others possibly pass beyond them in order to find a climate similar 

 to that which they have left. 



It has recently been ascertained that some of the birds that are 

 found in the north of Europe and have hitherto not been known to 

 exist in America, migrate from the polar regions, along the Rocky 

 mountains sometimes as far south as Mexico and in their spring mi- 

 grations return by the same route. The Magpie, [Corvus Pica,) 

 and the Bohemian wax-wing, {Bomhycilla garrula.) and a few oth- 

 ers, are of that number. Several other birds, peculiar to the Amer- 

 ican continent, never visit the cultivated districts of the United 

 States, but take the same course in their annual migrations ; among 

 these are the black water-ousel, (^Cinclus Pallassii, Tem.) the eve- 

 ning Grosbeak, (^Fringilla Cooperi^ Clarke's Crow, {Corvus col- 

 umbarius,) and the Columbia Jay, a most splendid bird, figured by 

 Anderson, rivalling in beauty the bird of Paradise. The spotted 

 thrush of Latham, {Turdus ncevius,) the arctic Blue-bird, (Erythaca 

 arctica, Swain.,) the Emberiza picta, Swain., and the saffron head- 

 ed Troophial, [Icterus xanthocephalus, Bon.) are also of this num- 

 ber. Those birds only, that breed in the arctic circle visit both Con- 

 tinents. It is computed that out of almost four hundred and fifty 

 species already known in North America, only twenty seven land, 

 and eighty one* water birds are natives of both continents ; conse- 



* This number has been considerably increased since the publication of Rich- 

 ardson and Svvainson's Fauna Boreali-Americana, in which it is to be feared the 

 mania for adding new species of birds has been indulged to a considerable extent. 



