3io THE BIRDS 



often selected. A neat circular hole is drilled in the wood, and 

 the shaft, at first horizontal, soon turns downwards, descending to 

 the depth of about a foot. As the birds (both parents help in the 

 excavation) proceed with their boring operations they gradually 

 enlarge the shaft so that when finished it has somewhat the form 

 of a long-necked bottle; 



When searching for insects in the bark of a tree the Woodpecker 

 usually begins at the foot and ascends in spiral fashion, eagerly 

 examining every crack as it goes. It clings to the bark with its 

 stout hooked claws, and further supports itself with its stiff tail 

 feathers, while the head swings backwards and forwards with 

 marvellous rapidity on the strong, muscular neck, and the hard, 

 wedge-shaped bill strikes the tree with hammer-like regularity. 

 The Green Woodpecker (Picus viridis), the Great Spotted Wood- 

 pecker (Dendrocopus major) and the Lesser Spotted Woodpecker 

 (D. minor) are the British representatives of the family. 



The Wrynecks differ from woodpeckers in having soft tails 

 without stiff feathers. They nest in holes in trees, taking advantage 

 of those already formed instead of carving them out for them- 

 selves like their more industrious allies. From its curious habit 

 of twisting the head almost completely round, as it sits at the 

 mouth of its hole or on a branch near by, the bird has gained its 

 popular name " Wryneck " ; while from the hissing sound it 

 makes when disturbed in the nest it is sometimes called the " Snake- 

 bird." It is also locally known as the " Cuckoo's Mate " or 

 " Cuckoo's Messenger," apparently because it usually arrives on 

 our shores a few days in advance of the cuckoo. 



The Passeres, or Perching Birds, are the most highly organised 

 order of their class. In numbers they exceed the birds of any 

 other order; some five thousand five hundred species have been 

 named more than half the birds known. The majority are of 

 small size, the foot is essentially adapted for perching, and the 

 voices are more perfect than in any other order of birds. All 

 the true song-birds are included in this order though all perch- 

 ing birds are not gifted with melodious voices and the Passeres 

 are classified as the Acromyodi, or singing birds, and the Mesomyodi, 

 or songless birds, but the division is based upon the structure of 

 the lower larynx, or syrinx, rather than upon the quality of the 

 birds' voices. 



