Fi«. 49. Yellow 

 Wagtail amid 

 grasses. 



Photographed from 

 life by Cherry and 

 Richard Keartou. 



Fig. 50. Male Bob-white 

 (Colinus virginiariiis) on its 

 nest. Highly-developed pic- 

 ture-pattern, based on full 

 obliterative shading. 



Photographed from life by 

 Maimfielf S. Crosby. Courtesy of 

 "Bird Lore." 



