68 A PRACTICAL HANDBOOK OF BRITISH BIRDS. 



and form a narrow, somewhat ill -defined breast-band ; rest of 

 under-parts, including under tail-coverts, axillaries and under 

 wing-coverts white with narrow bars of brown ; tail brown with 

 narrow, and sometimes very faint, bars of white or whitish, becoming 

 on inner portions of inner webs wider, whiter and more tooth -like ; 

 primaries and secondaries dark brown with tooth -like white marks 

 on edges of outer and inner webs, smaller and often spot-like on 

 outer and larger and tooth-like on inner webs ; primary-coverts 

 as primaries ; greater and median coverts mostly uniform brown 

 with a few white spots varying but usually on outer webs of outer 

 feathers ; lesser coverts brown with narrow white fringe. This 

 plumage is acquired by complete moult July-Sept. Summer. — 

 Apparently no moult and little change by abrasion. 



Nestling. — (Not examined.) 



Juvenile. — leathers of body, greater, median and lesser wing- 

 coverts of loose structure especially on head, throat, under and 

 upper tail -coverts but otherwise not quite so loose as in other Owls. 

 Crown mouse-brown, feathers tipped greyish-white ; nape mouse- 

 brown, feathers with whitish centres ; mantle mouse-brown ; 

 scapulars and wing-coverts white barred brown ; upper tail-coverts 

 same with narrower bars ; facial disk greyish -white and black- 

 brown round eye with outer ring of dark mouse-brown ; breast, 

 belly and sides greyish -white barred pale brown ; under tail-coverts 

 white ; wing- and tail-feathers as adult. 



First winter. — Not to be distinguished from adult except that 

 wing- and tail-feathers are more worn and paler brown at tips. 

 The juvenile body -plumage and wing -coverts are moulted July-Sept. 



Measurements and structure. — (J wing 225-236 mm., tail 1 70-186. 

 tarsus 22-29, bill from base of feathers 21-25 (9 measured). 2 wing 

 227-242. Primaries : 3rd longest, 4th sometimes as long, some- 

 times 1-6 mm. shorter, 2nd 7-10 shorter, 1st 38-47 shorter, 5th 

 15-27 shorter ; 2nd and 3rd clearly and 4th less clearly emarginated 

 outer webs ; outer edge of 1st primary and of emarginated portions 

 of 2nd to 4th with very short serrations. Outer secondary about 

 equal to 10th primary, rest becoming longer and longest about 

 equal to 7th primary, tips sharply rounded. Tail much rounded, 

 outermost pair of feathers being 20-40 mm. shorter than central 

 pair, 12 feathers, tips rounded. Under tail -coverts about half as 

 long as tail . Tarsi and toes covered with feathers . Rest of structure 

 as Snowy Owl. 



Soft parts. — Bill yellowish ; claws blackish -brown ; iris bright 

 yellow. 



Characters and allied forms. — For differences of S. u. caparoch 

 see under that form ; S. u. tianschanica (Tianshan) is dark like 

 S. u. caparoch on upper-parts but bars on under-parts are narrow 

 as in S. u. ulula, though darker ; S. u. pallasi (Siberia) has rather 

 paler upper -parts than S. u. ulula. Spotted upper -parts, barred 



