xxxm THE BEAKS OF BIRDS 291 



through the fingers. The end of the mandible, too, is full of 

 nerves, which enables the bird to distinguish the soft and minute 

 substances on which it feeds without seeing them. The oyster- 

 catcher, which feeds on shell-fish and similar food, has a bill 

 with hard, sharp points, with which it can dig into and break 

 the strong coverings of its prey ; no tool could be made to 

 answer the purpose better. The curlew's long curved bill is 

 also a perfect implement for worming out the sea-slugs, which 

 it extracts from the wet sands. The birds that live chiefly on 

 the insects and water-plants which are found in swamps and 

 muddy places have their feet of great size and length, which 

 enables them to walk and run over muddy and soft places with- 

 out sinking. The water-hen and water-rail, indeed, often run 

 along the floating leaves of the water-plants without bearing 

 them down by their weight. The bald coot, too, a bird that 

 lives almost wholly in muddy places, has its feet and toes formed 

 purposely for running on a soft surface. How different from 

 the strongly retractile talons of the hawk and owl, made pur- 

 posely to seize and hold their struggling prey. 



Thus also the beak of these carnivorous birds is formed for 

 tearing and rending, while the strong wedge-shaped mandibles 

 of the raven and carrion-crow are the best possible implements 

 for the half-digging, half-cutting work which they are called 

 upon to perform in devouring the dead carcasses of large animals. 

 The goosander and merganser, which feed principally on small 

 eels and fish, have a row of teeth-like projections inside their 

 bill, which, slanting inwards, admits of the easy entrance of their 

 slippery prej% but effectually prevents its escape ; while the cor- 

 morant, whose food consists of larger fish, instead of these 

 numerous teeth has a strong curved beak, well fitted for holding 

 the strongest sea-trout or haddock. Put your finger into the 

 bill of a common duck, and you will see how easily it goes in, 

 but how difficult it is to draw it out again, in consequence of 

 the sloping projections, by means of which the bird is enabled 

 to hold worms and snails. No bill but that of a crossbill could 

 cut and divide the strong fir-cones from which it extracts its 

 food. The common woodpecker bores holes with its strongly- 

 tipped wedge-shaped bill in the hard beech-trees, with a pre- 

 cision and regularity not to be excelled by the best carpenter ; 

 while with its long worm-like tongue it darts upon and catches 



