624 SYSTEMATIC SYNOPSIS. — RAPTORES — STRIGES. 



which is thus set askew. The facial disc varies in size and perfection, being largest, most 

 circular, and most completely radiating from the eye as a centre in those species in which the 

 ear-conch is best developed. These two characters would therefore seem to go together, and 

 they are not correlated with presence or absence of plumicorns — an obvious but trivial differ- 

 ence, which carries little weight in classification. Inner toe shorter than middle, and middle 

 claw not pectinate. The extent of feathering of the feet varies with almost every genus. It 

 proves advisal)le to make the foregoing main characters the basis of a division of Strigidce into 

 two subfamilies, Strigince and Biihonince. 



Analysis of Subfamilies and Genera. 



StriginjE. Eye centric in large complete circular disc, and ear-conch larger than eye, with well-developed oper- 

 culum ; ear-parts more or less unsymmetrical. Strictly nocturnal. 

 Plumicorns absent ; cere short. 



Ear-parts subsymmetrical. Large : length over 12 inches ; wing 15 or less ; tail under 10 ... . Strix 

 Largest : length over 20 inches ; wing IG or more ; tail over 10 . Scotiaptex 



Ear-parts as3Tnmetrical. Small : length under 12 inches Nyctala 



Plumicorns present ; cere longer than rest of culmen. Ear-parts asymmetrical As^o 



BuBONiN*. Eye eccentric, nearer top tlian bottom of more or less incomplete disc, and ear-conch not larger than 

 eye, without developed operculum, symmetrical. Not strictly nocturnal. 

 Plumicorns present, well-developed. 



Very large : length over 18 inches ; tail about § the wing Bubo 



Small : length under 12 inches ; tail about § the wing Megascops 



Plumicorns present, rudimentary. Very large : length over 18 inches. Wliite Nyctea 



Plumicorns absent. 



Tarsus full-feathered. 



Tail graduated. Length over 12 inches. Hawk-like Surnia 



Tail rounded. Length much under 12 inches. Arboreal Glaucidium 



Tarsus naked or scant-feathered. 



Length under 8 inches. Arboreal Micropallas 



Length over 8 inches. Terrestrial Speo/y/o 



A'SIO. (Lat. asio, a kind of horned owl.) Eared Owls. Marsh Owls. Skull and ear- 

 parts more or less unsymmetrical : conch of immense size, about as long as skull is high, fur- 

 nished with a movable operculum for its fall length. Eyes centric in perfectly developed facial 

 disc. Plumicorns more or less developed. Nostrils at edge of cere, which is somewhat inflated, 

 and longer than chord of culmen beyond it; bill rather weak. Wings about twice as long as 

 tail, pointed, 2d primary usually longest, only 1 or 2 primaries emarginate on inner webs. 

 Feet closely feathered to ends of toes. Of medium size ; our species 12.00-16.00 long. Em- 

 bracing about 12 species, and nearly cosmopolitan. Our Long-eared Owl is decidedly difi'er- 

 ent from that of Europe, Asio otus, but the Short-eared has not been satisfactorily distinguished 

 from the almost cosmopolitan A. accipitrimis. 



Analysis of Subgenera and Species. 



Plumicorns long, many-feathered {Asia proper) wilsonianus 



Plumicorns short, few-feathered {Brnchyotus) accipiirinus 



A. wilsonia'nus. (To A. Wilson. Figs. 56, 428.) American Long-eared OwL. Ear- 

 tufts conspicuous, about as long as middle toe and claw, of 8-12 feathers. First primary only 

 emarginate on inner web. Upper parts brownish-black, minutely mottled with grayish-white, 

 and variegated with the tawny of basal portions of the feathers which comes to the surface 

 here and there; general effect dark, quite different from the tawny streaking of A. otus of 

 Europe. Under parts confused blackish-brown, grayish-white and tawny; on breast marbled 

 in large pattern, for the rest with dusky shaft-lines throwing off dusky cross-bars (several on 

 each feather) on a whitish ground, and the tawny bases of the feathers showing more or less ; 

 feet and crissum mostly immaculate, tawny or whitish. Quills blackish -brown, regularly 



