WITH THE BIRDS IN WALES 147 



hills. On the way up, which was all hill work, I 

 disturbed a pair of Wood Wrens, and eventually found 

 their unfinished nest, which was built amongst dead 

 leaves in a little strip of woodland. Apart from any 

 other consideration, a Wood Wren's nest may be told 

 by the lining, which is composed of dried grass and 

 horsehair in small quantities, though I have seen 

 this latter material absent altogether. It never has 

 feathers, as its congeners the Willow Wren and Chiff- 

 chaff always have. 



A little higher up this wooded glen I drove a Green 

 Woodpecker from her nest-hole by smartly tapping 

 the tree containing her. I first discovered this nest 

 by seeing innumerable chips under the tree. I do 

 not think, indeed, that Woodpeckers ever remove the 

 chips, no such case having come under my own 

 observation ; but when any of the Tit family cut out 

 or enlarge a hole in any way they always remove the 

 tell-tale pieces to some distance. Further, you may 

 be quite certain that the tree a Woodpecker chooses 

 is rotten inside, even if outwardly it shows no sign 

 of decay ; and in the case of the nest found to-day 

 the bird had to chisel its way through some three 

 inches of sound wood, which must have been an 

 arduous undertaking. On the other hand, I have 

 found nest-holes of these species in such rotten wood 

 that it could be torn away with the hand. Whilst 

 examining the nest in question I heard the well- 

 known cry of a Pied Flycatcher, and looking round, 

 perceived a male bird sitting on a bough close to me. 

 He looked simply charming as he sat on that alder 

 branch surveying me critically. I could not find his 



