26 THE FEATHERED TRIWiS. 



many eilbrts must lie have made to realise any approach to such complieatcd conditions ! 

 How far would his most successful result be distant from the bill of a bird ! 



And then, let it be remembered how the bill A'aries in structure, as in purpose. The 

 bill of the domestic fo\\l has onlj' to pick up its food, to arrange its nest, to preen its 

 feathers, and occasionally to act as a weapon, but in the tribe to which this bird belongs 

 great di\'crsities may be easily detected, even in the bill. Still greater is the diffei-ence in 

 other circmnstances. Wliy, for instance, have the curlew, the plover, and the woodcock, 

 such a length of bill ? It is, that they may dig up the worms and caterpillars which lie 

 far beneath the surface of the earth. Nor is this all ; for each of these creatures, like all 

 others resembling them, is pro\ided with the means of distinguishing its prey, soft as it 

 may be, even among the mud that is equally soft. " It is doubtful," says Macculloch, 

 whose invaluable work abounds with similar facts, " if the most delicate human finger 

 coidd feel the food of a woodcock where it lies. But there is e\en more of contrivance, if 

 I mistake not, in this provision. The nerves arc large beyond all apparent necessity ; 

 utterly disproportioned to a nerve of touch in any other animal body. It was necessary 

 that the point of the bill should be tough and firm ; and the magnitude of the nerves 

 forms a compensation for this." 



Other provisions are no less remarkable. The .sjjoonbill ap]icars cx^iressly designed for 

 gathering shell-fish. The small flexible strap, and the reflected arch of the sjvoset's biU 

 prepare it specially for living on spawn. The oyster-catcher has an axe-shaped bill, that 

 it may cleave the shells of the moUusks Avhicli are destined for its prey. The cross-bill is 

 no less dexterous in plucking the scales from the fir-cones. And the shear-bill has that 

 part of the structure consisting of two pieces extremely unequal, the lower mandible 

 being long, and projecting far beyond the upper, into which the latter falls like the razor 

 into its haft, that it may fly with its lower mandil)le cutting the water, and there readily 

 capture the creatures intended for its food. 



The horn, which mvests the two mandibles, serves the place of teeth, and is sometimes 

 prickled, so as to represent them. Its form, like that of the mandibles, is greatly diversi- 

 fied, according to the nature of the food of which each species partakes. The tongue 

 haa but little muscular substance, and, in the majority of birds, but little debcacy. 



The organ of smell, hidden in the base of the beak, is very sensible. The size of the 

 osseous openings governs the form of this part, and the various coverings, as cartilages, 

 membranes, and feathers, which straiten these openings, have nn influence on the 

 strength of the smell, and on the sort of nourishment. 



The semicircular canals of the ear arc large, and lodged in a part of the skidl, where 

 they are surrounded on all sides with air-ca^dties. Night-birds alone have a large 

 external ear, \\liich is not so prominent as that of quadrupeds. This opening is generally 

 covered ynth barbed feathers, more fringed than the others. 



