CUAP. xxxin.] INSTINCT IN MRDS. 255 



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, who 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 prey, 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 precision and 

 regularity not to be excelled by the best carpenter; while with 

 its long worm-like tongue it darts upon and catches the small 

 insects which take refuge in the chinks and crevices of the bark. 

 The swallows, who catch their insect prey while flying at speed 

 in the air, are provided with large wide-opening mouths, which 

 enables them to capture the swiftest flying moth or midge. In 

 fact, if we take the trouble to examine the manner of feeding and 

 the structure of the commonest birds, which we pass over without 

 observation in consequence of their want of rarity, we see that 

 the Providence that has made them has also adapted each in the 

 most perfect manner for acquiring with facility the food on 

 which it is designed to live. The owl, that preys mostly on the 

 quick-eared mouse, has its wings edged with a kind of downy 

 fringe, which makes its flight silent and inaudible in the still 

 evening air. Were its wings formed of the same kind of 

 plumage as those of most other birds, it is so slow a fli,-r that 

 the mouse, warned by the rustling of its approach, would escape 

 long before it could pounce upon it. The heron has also a 

 quantity of downy plumage about its wings, which are also of a 

 very concave form, and the bird alights in the calm pool without 

 making a ripple, and whilst standing motionless, knee-deep in the 

 water, it is almost invisible in the gloom of evening, owing to 



