l86 THE BIRDS OF THE BRITISH ISLES. 



white, the colour deepest on the flanks, and the axillaries are 

 distinctly yellow. The bill, legs and irides are brown ; the legs 

 much paler than those of the Chiffchaff. The sexes are alike, 

 and after the autumn moult the birds are yellower, whilst the 

 young are still more decidedly yellow. In the Willow-Warbler 

 "the first to fifth primaries are emarginate ; in the Chiffchaff the 

 sixth is included. Length, 4*5 ins. Wing, 2*5 ins. Tarsus, 

 7 in. 



The Northern Willow-Wren is a much greyer and whiter 

 bird. It passes north after our birds have begun to nest, but 

 it must be remembered that plumage varies as also do times 

 of arrival. 



Arctic Willow-Warbler. Phylloscopus borealis (Bias.). 



The Arctic or Eversmann's Warbler, which breeds in northern 

 Norway, Russia and eastern Siberia, and is only known to 

 winter in southern Asia, has been obtained once in the Orkneys 

 and once in the Shetlands. It is a greenish brown bird, with 

 a broad yellow eye-stripe ; white, slightly tinged with yellow 

 beneath, and with two yellowish white bars across the wing. 

 Length, 47 ins. Wing, 27 ins. Tarsus, '8 in. 



Wood- War bier. Phylloscop-us sibilatrix (Bech.). 



As a summer resident the Wood-Warbler or Wood- Wren 

 (Plate 76) comes late and departs early, reaching the south 

 about the middle of April, but is seldom generally distributed 

 before May. It occurs in suitable woodlands throughout Great 

 Britain, but is local in Ireland and absent from many of the 

 Scottish islands, though it has occurred on passage in the 

 Shetlands. The typical race or its southern form is found 

 throughout Europe except in the far north ; it winters in Africa. 



Of the three leaf-warblers this is the most arboreal and, from 

 the nature of its haunts, the most local ; it delights in the more 



