CHAPTER XXII. 



PHYSICAL FEATURES OF BIRDS. 



As to the physical features of a typical bird, we may 

 consider the uses of the bill, the feet, the tail, and the 

 meaning of the coloration of birds. We are to understand 

 that the biologist does not think that things just happen, 

 and have no meaning nor use in the great scheme of life. 

 No life trait appears without the preceding stimulus to 

 that form of activity; hence under the operation of this 

 law all those features characteristic of an individual are 

 seen to be fraught with meaning to the individual in the 

 ease or success with which he "gets along in the world." 



Fig. 99.— Conirostral bill of a canary. Fig. 100.— Falcate bill of cross-bill. 



The BUI. 



The chief office of the bill is to take the place of the 

 hand, which the bird lacks. It really belongs to a biped 

 which is without arms or hands, and so must make the 

 bill do much of the work of both these members. It is 

 the organ of prehension, of defense, and is of use in making 



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