I IO 



Allen, Origin and Distribution of N. A. Birds. I April 



cumboreal and mainly subarctic ; six others are snbcosmopolitan, 

 while two only are American, namely, Micropallas and Sfieo- 

 tyto, both of which have a rather restricted North American 

 range. The latter doubtless reached North America from two 

 sources, the West Indies, from which the Florida stock came, 

 and Mexico, from which the western stock was derived. 



Conurus, the only representative of the great order Psittaci, 

 is of course only a northern outlier of the numerous group of trop- 

 ical American Conures. 



Our Cuckoos are all of tropical American origin, only the 

 single genus Coccyzus having an extended North American dis- 

 tribution. Geococcyx is doubtless of Mexican origin. Our 

 single genus of Kingfishers is subcosmopolitan. 



Of our eight genera of Woodpeckers two, Picoides and Dryo- 

 bates, are circumpolar, one being subarctic and the other of wide 

 distribution ; three ai - e distinctively North American, while three 

 others range at large over most of the two Americas. 



Of the three genera of Swifts one, Chcztura, is nearly cosmo- 

 politan, one is exclusively North American, and one ranges over 

 a large part of both the American continents. 



All of the five genera of Goatsuckers, if Antrostotnus be recog- 

 nized as separable from Caprimulgus, are exclusively Ameri- 

 can ; one only, Phalcenoptilus, is restricted to North America, 

 while Nyctidromus does not pass much beyond the Rio Grande. 



Seven of the ten genera of Hummingbirds are essentially tropi- 

 cal, barely extending within our limits, while only one ranges 

 over a very large part of the continent. Of the fourteen species, 

 only one is eastern. 



The Tyrannidas, though preeminently a group of the American 

 tropics, is represented by ten genera in North America ; five of 

 them, however, are scarcely entitled to rank as North American, 

 and of the remaining five, only two, Contofius and Etnpidonax, 

 reach the cold temperate latitudes. 



The only American representative of the numerous Old World 

 family Alaudidaa is the genus Otocoris, which ranges through- 

 out the greater part of the northern hemisphere. 



The Corvidae are represented by eight genera, three of which 

 are cosmopolitan and one, Xanthoura, is tropical. The other 

 four are not only almost exclusively North American, but two of 

 them are limited to the western half of the continent. 



