Species and Races. 1. =B. virginianus.= Lower parts transversely barred with black, and without longitudinal stripes. Above without longitudinal stripes on the anterior portions. _a._ A conspicuous patch of white on the jugulum; lining of the wing immaculate, 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. _Hab._ Atlantic Province of North America … var. _virginianus_. Lighter tints of the plumage prevailing; face dirty or fulvous white. All the colors lighter. _Hab._ Western Province of United States, and interior regions of British America. Upper Mississippi Valley in winter (Wisconsin, Hoy; Pekin, Illinois, Museum, Cambridge) … var. _arcticus_. 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. _Hab._ Littoral regions of northern North America, from Oregon northward, and around the northern coast to Labrador … var. _pacificus_. _b._ No conspicuous patch of white on the jugulum, which, with the lining of the wing, is distinctly barred with blackish. Wing, 12.00; tail, 7.50; culmen, 1.00; tarsus, 2.10; middle toe, 1.85. Colors much as in var. _virginianus_, but more densely barred beneath, the dark bars narrower and closer together. _Hab._ South America … var. _magellanicus_.[27] 2. =B. mexicanus.=[28] Lower parts longitudinally striped with black, and without transverse bars. Above with longitudinal stripes on the anterior portions. Wing, 11.20–12.00; tail, 6.00–6.50; culmen, .90; tarsus, 2.00; middle toe, 1.95. _Hab._ Middle and South America generally. SUBGENUS NYCTEA, STEPHENS. _Nyctea_, STEPHENS, Cont. Shaw’s Zoöl. XIII, 62, 1826. (Type _Strix nyctea_, LINN. _N. Scandiaca_, LINN.). Species and Races. 1. =N. scandiaca.= _Adult._ Color pure white, more or less barred transversely with clear dusky, or brownish-black. _Male_ sometimes almost pure white. _Downy young_, sooty slate-color. Wing, 16.00–18.00; tail, 9.00–10.00. Dusky bars sparse, narrow, umber-brown. _Hab._ Northern parts of Palæarctic Realm … var. _scandiaca_.[29] Dusky bars more numerous, broader, and clear brownish-black. _Hab._ Northern parts of Nearctic Realm … var. _arctica_. Bubo virginianus, var. virginianus, BONAP. GREAT HORNED OWL.