﻿BIRDS OF PREY. OWLS. 



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and research are alone necessary to give the same sta- 

 bility to the minor divisions. In the mean time we 

 shall endeavour to make some approximation to this 

 object by exercising our own judgment as to the rank 

 of the subordinate types, that is, all such as exhibit 

 those representations above alluded to ; without pre- 

 suming, however, to attach to our opinion that weight 

 which further knowledge and analysis can alone impart. 



(257.) The Strigid^e, or Owls, exhibit the full 

 development of that singular ruff of close-set feathers 

 round the head, the first indications of which are seen 

 in the henharriers (Circus C). Their nocturnal habits, 

 their large eyes, singularly shaped ears, and soft downy 

 plumage, are well known. This structure is admirably 

 adapted to their peculiar economy. Great powers of 

 sight and hearing are absolutely essential to these birds, 

 whose habits are nocturnal, more particularly as they 

 hunt after many small quadrupeds which only venture 

 from their retreats after sunset. No sound in the air 

 should tell the approach of the owls : their flight, by the 

 peculiar construction of the wing feathers, is, therefore, 

 rendered noiseless, and they come upon their prey 

 silently and surely. The wings of the goatsuckers 

 {Caprimulgidce) alone, of all other birds, exhibit a 

 similar conformation. In both these, the tips of the 

 external bars of the outermost quill feathers, instead of 

 lying flat upon each other, in the ordinary way, are 

 detached and curved outwards, so as to resemble the 

 teeth of a fine saw ; hence it follows that when the air 

 is beaten by wings so formed, there is no reverberation. 

 The opposite extreme of this structure is seen in the 

 gallinaceous birds, where the external barbs are very 

 stiff, and pressed close upon each other : this formation 

 of wing causes the air to be suddenly and abruptly ex- 

 pelled from beneath it, and occasions that loud whirling 

 noise, often startling to the unprepared pedestrian, 

 with which the partridge ascends from the ground and 

 seeks refuge in flight. The whole structure, in fact, of 

 the wings of the owl is evidently intended to promote a 



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