THE WILLOW-WARBLER. 305 



Juvenile. Male and female. Whole upper-parts brown tinged 

 olive (browner than adult) ; eye-stripe yellow ; ear-coverts pale 

 brown streaked buff and yellow ; chin and throat dull buffish- 

 yellow ; upper-breast dusky buff ; lower-breast and belly very 

 pale yellow ; under tail-coverts rather more buff ; flanks whitish- 

 buff ; axillaries pale yellow. 



First winter. Male and female. Like adult but slightly 

 more yellowish-brown, not so greenish on upper -parts and much 

 yellower on under -parts, throat and breast being deeper yellow 

 and belly only shade paler instead of white, sides of breast and 

 flanks deeper yellowish-buff. The juvenile body-feathers are 

 moulted July and Aug. but not wing-coverts, wings or tail. First 

 summer. Like adult and moult same. 



Measurements and structure. <$ wing 64-70 mm., tail 49-52, 

 tarsus 19-21, bill from skull 10-11 (12 measured). $ wing 60-66. 

 Primaries : 1st 3-6 mm. longer than longest primary -co vert, 

 3rd and 4th longest and equal, 5th 1-3 shorter, 6th 5-8 shorter 

 7th 8-11 shorter, 2nd usually between 5th and 6th sometimes 

 as short as 6th occasionally as long as 5th ; 3rd to 5th emarginated 

 outer webs. Rest of structure as Chiffchaff. 



Soft parts. Bill brown with base of lower mandible paler ; 

 legs and feet pale to dark brown ; iris hazel. 



CHARACTERS AND ALLIED FORMS. For differences of Ph. t. evers- 

 manni see under that form, and of Chiffchaff see under that species. 



FIELD -CHARACTERS. Differs from Chiffchaff in being rather- 

 larger, and having brown legs and plumage tinged with yellow. 

 Less restricted to woods and coppices, and much more abundant. 

 Song a sweet warble rising at first and then descending until it 

 seems to melt away. Alarm-note a plaintive " hoo-id " similar 

 to that of Chiffchaff. 



BREEDING-HABITS. Breeds among grass in hedge-bottoms, by 

 road sides or open glades in woods. Occasionally in low bush, 

 on trellis or in ivy on wall, but normally nesting on ground, though 

 occasionally recorded as much as 14 or 16 ft. aboveit. Nest. Domed 

 with neat entrance at side, built of green moss, inter-woven stalks, 

 grasses, sometimes bracken, lined freely with feathers almost 

 invariably. Eggs. Normally 6-7, rarely 8 or 9 but in late layings 

 4 and 5 may be found. Variable : some finely freckled light 

 red : others blotched light red-brown ; a third type boldly spotted 

 dark sienna-brown. 50 British eggs average 15.2 x 12.3 mm. 

 Breeding-season. About end April and first half Ma^. Most 

 birds are apparently single brooded, but a few may be found 

 nesting in June and July, Incubation. Normally 13 days (J. H. 

 Owen and W. Evans), by hen only. Fledging-period. Variable, 

 12-16 days as a rule (S. E. Brock and J. H. Owen.) 



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