﻿46 



ON THE CLASSIFICATION OF BIRDS. 



darting with incredible rapidity upon it, before their 

 presence has been discerned, the alarm note given, and 

 a retreat effected. A great deal has been written, and 

 now rendered familiar to every one by our cheap com- 

 pilations, on the powers of sight in the falconine tribes ; 

 but those of the swallows seem to have been quite over- 

 looked. It is, nevertheless, difficult to say which is the 

 most astounding, the far-sightedness of the former, or 

 the instantaneous and complicated discernment of the 

 latter. The swallow is proverbially the swiftest flyer in 

 the feathered creation ; and yet, in the full career of its 

 course, it is entirely intent upon quite another object 

 than that of flight. While darting through the air at 

 the rate of three miles a minute, it is looking on the right 

 hand and on the left, sideways, upwards, and down- 

 wards, for its food. The insects it preys upon are 

 often exceedingly minute — sometimes flying above or 

 below the level of the swallow's flight ; and yet they are 

 seen, captured, and swallowed, without any diminution 

 of the prodigious rate at which the bird is flying : nay, 

 more, any one who attentively watches the swallow skim- 

 ming over a meadow in summer, will perceive that it 

 will capture two or even three insects in such quick suc- 

 cession as to convince us the bird must have had them 

 in his eye, to use a colloquial expression, all at once, 

 and that the whole are caught and swallowed in as many 

 moments. The faculty of vision, in short, in these 

 birds, is fully as much developed as in the falcons, al- 

 though in a very different way ; the one being long, and 

 the other quick sighted, and both, to a degree, perfectly 

 unexampled in the animal creation. BufFon has used 

 his eloquence very happily in expatiating on the im- 

 mense distance at which the hawk can distinguish his 

 prey. He affirms, apparently with truth, that a hawk 

 can distinguish a lark, coloured like the clod of earth 

 upon which it is sitting, at twenty times the distance at 

 which it would be perceived either by a dog or a man ; 

 but when he asserts that a kite, soaring beyond the reach 

 of our sight, can see the lizards and mice on the fields 



