216 A PRACTICAL HANDBOOK OF BRITISH BIRDS. 



First Winter. Like adult. The juvenile body -feathers, wing- 

 coverts and innermost secondaries are moulted in Aug. -Oct., but 

 not primary-coverts nor rest of wing-feathers or tail-feathers. 



Measurements and structure. $ wing 62-67 mm., tail 58-62, 

 tarsus 15-16, bill from skull 14-17 (12 measured). $ wing 59-67, 

 bill 1317. Primaries : 1st about twice primary-coverts and about 

 half 2nd primary, 4th and 5th longest, 6th usually 1 mm. shorter 

 but sometimes as long, 3rd 1-3 shorter, 2nd 9-12 shorter and equal 

 to 8th or 9th ; 4th to 6th clearly emarginated outer webs. Secon- 

 daries equal 10th primary, tips sloped off to blunt point. Tail 

 graduated, forming wedge-shape, each feather stiff and strong and 

 tapering towards tip to a point. Bill fine, compressed, decurved 

 and sharp-pointed. No rictal bristles. Tarsal joint hidden by 

 feathers. Toes, three in front, one behind. Claws strong and 

 much curved, hind claw rather longer than hind toe. 



Soft parts. Bill dark brown, lower mandible pinkish ; legs 

 and feet pale brown ; iris dark brown. 



CHARACTERS AND ALLIED FORMS. For differences of C. f. familiaris 

 see under that form. C. f. macrodactyla (France, Germany, 

 Hungary) is intermediate in coloration between C. f. familiaris 

 and C. f. brittanica, and is much like latter but brown of upper- 

 parts and especially rump is less rufous, C. f. corsa (Corsica) is 

 like C. f. macrodactyla but larger and more distinctly streaked on 

 mantle, C. f. bianchii (Kansu) and C. f. tianschanica (Tian-Shan) 

 differ slightly in coloration of upper-parts, C. f. khamensis (Mekong, 

 Tibet) and C.f. nipalensis (Nepal, Sikkim) have darker under-parts, 

 C. f. hodgsoni (Kashmir) is much like C. f. macrodactyla, but 4th 

 primary has no light mark on outer web, C. f. japonica (Japan) 

 is much like C. f. familiaris with colours of upper-parts more 

 contrasted. The species Certhia brachydactyla represented by 

 several forms, often living side by side with forms of C. familiaris 

 in Europe (but absent from British Isles) differs from C. familiaris 

 in having shorter hind claw, longer bill, dark spot on under wing- 

 coverts at base of 1st primary (usually absent in forms of C. f. 

 familiaris) and usually darker and less rufous upper-parts and 

 darker flanks. The stiff pointed tail and slender curved bill 

 distinguish Tree-Creeper from other British birds. 

 FIELD -CHARACTERS. Soberly coloured, mottled brown above and 

 silvery- white below, would often escape notice but for very charac- 

 teristic behaviour. Constantly hunting for insects, it ascends trunks 

 and limbs of trees, and more rarely walls, by jerky leaps, then flies 

 obliquely downwards to foot of another tree and again ascends. 

 Stiff long tail-feathers pressed against bark in climbing. Call-note 

 a weak " zee-zee." Song " zee, zee, zee, pee. zee, zee, zissy, pee," 

 deliberate at first but quicker as it proceeds, is uttered during pauses 

 in ascent. During winter often associates with bands of Tits and 

 Goldcrests. 



