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insects which at best are not harmful, and which possibly 

 may be beneficial." Forbes states that, " while the robin 

 is not so precious that we need make it an act of sacrilege 

 to show him the muzzle of a gun in a cherry orchard on 

 the other hand it would be an enormous blunder to wage 

 ourselves, or to permit others to wage, any general or indis- 

 criminate war against him." 



The robin depends for the most part on its acute vision 

 and agility to secure food. Its sharp eyes are quick to spy 

 out any lurking insect in a garden, and its horny beak is an 

 excellent organ for capturing such morsels, for it is im- 

 pervious to bites or stings. Birds are handicapped some- 

 what in feeding by the lack of claws or other seizing organs 

 on the front limbs ; but this is compensated for by the great 

 quickness which is associated with the use of the wings for 

 flight, and by the great flexibility of the neck. 



The feathers are admirably adapted for flight; being 

 light, yet with broad expanse; flexible, but stiff enough to 

 resist the air. The small barbs on either side of the main 

 shaft are provided with minute hooked barbels which bind 

 them together so as to make a broad flat surface; this may 

 be broken up repeatedly, yet on being smoothed over again 

 will be as firm as before. Within the body there are struc- 

 tural adaptations which make it light. The air sacs open- 

 ing from the lungs are good examples of such structures. 

 They lie beween the large muscles, among the internal 

 organs, and are even connected with cavities within the 

 long bones. In order that flight may be swift and sure, 

 the body must be rigid as well as light; there can be no 

 wavering or the flyer will fall. To secure greater rigidity 

 in the body, certain parts of the skeleton which consist of 

 separate bones in other vertebrates are firmly united in 

 birds. Each rib bears a projection (uncinate process) on 

 one side which overlaps the next rib, thus making the body 

 very firm during flight. Perhaps the most striking skeletal 

 adaptation for flight is the great keel on the sternum, which 

 gives attachment to the wing muscles. 



