268 VERTEBRATES. 



their whole structure is admirably adapted. The bill is long, 

 sharp, and powerful, and the formation of the feet and legs is such 

 that the bird is able to grasp the tree firmly irith the feet, wlile 

 swinging with the force of his whole body 

 against it. Another most singular point in the 

 Woodpeckers, is the method by which they are 

 enabled to thrust the tongue deep into the cre- 

 vices, and bring out^any insects that may hap- 

 pen to be there. The tongue is connected with 

 two elastic ligaments, which are inserted near 

 the juncture of the upper mandible with the 

 Woodpecker skull. From thence they sweep round the 



back of the head, and passing under the lower 

 mandible, enable the tongue to be thrust out a considerable dis- 

 tance. The tip of the tongue is sharp, and barbed with several 

 filaments, and more firmly to secure the prey, a kind of gummy 

 secretion causes those insects to adhere, that would be too small 

 to be impaled. 



It appears to be an erroneous opinion that these birds injure 

 trees. Their only object in pecking away the wood and bark, is 

 to get at the insects which they know are hidden within. Now 

 insects seldom or never bore into healthy wood, but a decayed 

 branch or stump is always full of .them, as is well known to the 

 entomologist. So the winged entomologist, when he perceives a 

 decayed branch, or finds an unsoimd spot in the trunk, immedi- 

 ately sets to work industriously, and is rewarded by finding plenty 

 of insects, which he draws out and demolishes, with more benefit 

 to himself, and possibly more good to others, than many human 

 entomologists can boast. . 



The Green Woodpecker, by far the most common, may be 

 often seen in woods, tapping the trees with wonderful rapidity, 

 the blows following each other something like the sound of a 

 watchman's rattle. It generally runs up the trunk of the tree in 

 a spiral direction, occasionally striking off large pieces of diy 

 bark. When it descends it still keeps its head uppermost. 



The Cuckoo. — The characteristic marks are these : the 



