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AVES 



Color. — (i) The chemical absorption colors have coloring matter 

 as a pigment or coloring solution. Colors thus produced are black, 

 red, brown, orange and yellow, rarely green, and never blue. Certain 

 red birds (plantain eaters, Miisophagidae) lose their red color in the 

 rain but regain it when dry. The pigment (turacin, a copper salt) 

 stains the water into which the animal goes for a bath. 



Fig. 199. Forms of beaks. After Claus. Forms of beaks {a, b, c, d, k, after 

 Naumann; g, i, m, 0, regne animal; /, from Brehm): a, Phoenicopterus antiquorum; b, 

 Platalea leucorodia; c, Emberiza citrinella; d, Turdiis cyaniis; e, Falco candicans; f, 

 Mergus merganser; g, Pelecanus perspicillatus; h, Recurvirostra avocetta; i, Rhynchops 

 nigra; k, Columba livia; /, Balaeniceps rex; m, Anastomos coromandelianus; n, Ptero- 

 glossus discolor; 0, Mycteria senegalensis; p, Fakinellies ignetis; q, Cypselus apus. 

 (From Daugherty. Courtesy of W. B. Saunders & Co.) 



(2) Another type of color production is by means of pigment 

 combined with structural peculiarities, such as ridges and furrows 

 in the surface of the feather itself. Thus we find produced blue, 

 green usually, sometimes yellow. In transmitted light, feathers 

 with these colors show the color of the pigment. 



(3) Metallic colors are found in the humming birds, dove, grackle, 

 starling, and peacock. The commonly accepted hypothesis is that 



