CHAPTER XV 



BIRDS. OBLITERATIVE COLORATION AND MASKING OF BILL AND FEET FOR 



OFFENSIVE PURPOSES 



UNDER this heading I shall include the pattern-bearing " pantaloons" 

 of hawks, the prevailing pale or bright coloration and occasional 

 counter shading of their tarsi and feet, and the various bright colors and 

 occasional flowerlike appendages of the bills of jacanas, gallinules, anhingas, 

 herons, etc. 



The spreading shields of leg feathers, or "pantaloons," worn by almost 

 all hawks and some owls, and almost peculiar to them, must naturally be 

 supposed to have some connection with their predatory grabbing-habits. 

 But what is the connection — what the function of these pantaloons? One 

 use they have, and a seemingly important one, is this : they act as masks of 

 the dangerous talons, by making them appear merely as spots merged into a 

 moving veil of patterned feathers. If the extended legs and feet were stark 

 and narrow, without adornment, they would be much more clearly visible 

 to the animal attacked. As it is, the deadly feet descend in a broad and 

 blurring haze of mottled feathers, which must certainly reduce the victim's 

 chances of successful dodging. The bold form of the hawk's long leg is 

 veiled by these tufted feathers, and still further concealed by the pattern of 

 spots or transverse bars which these feathers bear. On some species, such 

 as the Rough-legged Buzzards (Archibuteo) of the North, and the Harpy 

 Hawks (Spizaetus) of South America, the entire tarsus is concealed by feathers, 

 usually covered with bold patterns (sharply cut by transverse barrings in the 

 Harpy Hawks) ; but most species have the tarsus as well as the foot bare for 

 action. Most owls, on the other hand, have everything but the very claws 



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