ON NORTH AMERICAN ZOOLOGY. 195 



their congeners above-named seek by traversing many degrees 

 of latitude. Captain King observed some humming birds ho- 

 vering over the fuschiiS, which grow plentifully in the Straits of 

 Magalhaes, the ground being at the time covered withsnow. 



Insessores, Fissirostres. — The only species of the halcyonidce 

 which enters North America, is universally distributed from 

 Louisiana up to the 6Sth parallel : its winter being spent in the 

 southern parts of the United States and in the West Indies. 

 Few birds have given rise to more speculation than the swallows. 

 Marvellous stories of their hybernating in caverns or at the bot- 

 toms of lakes, were believed even recently by naturalists of repu- 

 tation, yet there is scarcely a seaman, accustomed to navigate 

 the, Mediterranean, who has not seen these birds migrating in 

 large flocks to or from the coast of Africa, accompanied by pre- 

 dacious birds of various kinds. Mr. Audubon has skilfully 

 availed himself of the great facilities which America offers for 

 tracing the migrations of birds, so as to put to rest for ever the 

 question of the hybernation of swallows. From his investiga- 

 tions, we are assured that the hirundo hicolor winters in the 

 neighbourhood of New Orleans, where it roosts at night in 

 hollow trees. Mr. Bachman also states, that this bird appears 

 in the neighbourhood of Charlestown in winter after a few 

 successive warm days. The other species winter in Mexico and 

 the West Indies ; and the hirundo purpurea and riparia, which 

 extend in summer to the northern extremity of the continent, 

 have a range southwards to the Brazils ; the former it is stated 

 by the Reverend Mr. Bachman breeding in the latter locality 

 during the winter of the northern hemisphere. A conjecture 

 that some species of birds might breed twice in the year in dif- 

 ferent climates was hazarded in the introduction to the Fauna 

 boreali-americana, but I am not aware of any direct testimony 

 to that effect having been adduced prior to the publication of 

 Mr. Bachman's paper. The caprimulgidce winter to the south- 

 ward of the United States. 



Rasores. — This is the least migratory of all the orders of 

 birds, yet the species are in general readily acclimated in lati- 

 tudes remote from their native haunts, and in fact it is from 

 these birds that man derives the greatest advantage in his do- 

 mestic economy. Our common poultry were originally brought 

 from warmer regions, and this furnishes another evidence of 

 abundance of proper food being more important than the tem- 

 perature of the atmosphere in regulating the distribution of the 

 feathered tribes, the dense covering of their bodies protecting 

 them well from the severity of northern winters. There is, 

 however, a limit to the range of each species, and it is found 



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