140 LOOSE WINGS. 



time: they never fly fast but when.they are excited, 

 and they very frequently scream as well as flutter, 

 showing thereby that they are in a state of unnatural 

 excitement that such flight is not their natural habit. 



And when we examine their structure, we find that 

 the whole body must act when they fly. The deep 

 forks or clefts in the sides of the sternum, render that 

 bone flexible ; the form of the furcal bone, which is 

 that of the letter Y more than that of an arch, and 

 with the branches not placed with that side to the 

 strain with which they would be stifiest ; and the 

 looseness of the blade-bone; all conspire to render the 

 socket of the hnmerus unsteady and capable of play 

 in all directions. The whole side of the animal thus 

 works in lessening the effect of the wing-stroke, and 

 at the same time fatigues the bird more than would 

 be done by a firm wing. The muscles are also, as 

 has been noticed, of less firm and enduring texture, 

 in proportion to their bulk. Thus the gallinaceous 

 bird is, by its structure, kept to its element as an 

 inhabitant of the earth, and rendered incapable of 

 soaring with the air-birds, to share either the gran- 

 deur of their flight, or the dangers to which they are 

 exposed on the wing. 



But while the loose and fluttering wings of these 

 birds keep them to their own element and place in 

 the world, they are not less adapted to their habits 

 and necessities there, than the swiftest and most 

 enduring wings are to their different element. We 

 have already mentioned how well they are suited 

 for escaping the foe or gaining the perch ; and the 

 looseness of the scapular socket is not the least beau- 

 tiful part of their adaptation. The haunts of the 

 birds are among shrubs, and bushes, and tall herbage, 

 and they have often to use their wings and get quickly 



