60 NORTH AMERICAN BIRDS. 



Vera Cruz, Mexico. Nothing is known as to any peculiarities of habit. 

 These are not probably different from those of the asio. 



Genus BUBO, Dum. 



Gen. Char. Size varying from medium to very large ; head with or without ear-tufts. 

 Bill black ; iris yellow. Two to four outer quills with their inner webs emargmated. 

 Third or fourth quill longest. Bill very robust, the lower mandible nearly truncated and 

 with a deep notch near the end ; cere gradually ascending basally (not arched) or nearly 

 straight, not equal to the culmen. Tail short, a little more than half the wing, slightly 

 rounded. Ear-conch small, simple, without operculum ; the two ears symmetrical. 



Subgenera. 



Bubo. Two to three outer quills with their inner webs emarginated. Ear- 

 tufts well developed; loral feathers not hiding the bill, and the claws and 

 terminal scutellte of the toes exposed. Lower tail-coverts not reaching the 

 end of the tail. (Type, B. maximus.) 



Nyctea. Four outer quills with their inner Avebs emarginated. Ear-tufts 

 rudimentary ; loral feathers hiding the bill, and claws and entire toes con- 

 cealed by long hair-like feathers. Lower tail-coverts reaching to end of the 

 tail. (Type, N. scandiaca.) 



The species of this genus are mostly of very large size, two of them 

 {B. maximus and N. scandiaca) being the largest birds of the family. They 

 are nearly cosmopolitan, and are most numerous in the Eastern Hemisphere. 



Subgenus BUBO, Dum. 



Bubo, DuM^RiL, 1806. (Type, Strixbuho, Linn. =5. maximus, Sibb.) 

 Bhinostrix, Kaup, 1849. (Type, Strix mexicana, Gmel. = B. mexicanus, RiDGW.) 

 Bliinoptynx, Kaup, and Ehenoptyitx, Kaup, 1857. (Same type.) 



Species and Races. 



1. B. virginianus. Lower parts transversely barred with black, and Avithout 

 longitudinal stripes. Above Avithout longitudinal stripes on the anterior por- 

 tions. 



a. A conspicuous patch of white on the jugulum ; lining of the wing im- 

 maculate, or only faintly barred. Wing, 14.00-16.00; tail, 8.00- 10.00; 

 culmen, 1.10-1.20; tarsus, 2.00- 2.20; middle toe, 1.95-2.10.. 



Rufous tints of the plumage prevailing; face dingy rufous. Hub. 

 Atlantic Province of North America .... var. virginianus. 

 Lighter tints of the plumage prevailing ; face dirty or fulvous white. 

 All the colors lighter. Hah. Western Province of United States, 

 and interior regions of British America. Upper Mississippi Valley in 

 winter (Wisconsin, Hoy ; Pekin, Illinois, Museum, Cambridge). 



var. at'cticus. 

 Dusky tints of the plumage prevailing; face dull grayish, barred with 

 dusky. All the colors darker, chiefly brownish-black and grayish-white, 

 with little or no rufous. Hub. Littoral regions of northern North 



