200 CALIFORNIA ACADEMY OF SCIENCES. 



By far the largest number of useful markings are in- 

 cluded under the ■ head of (B) Sematic Colors. As ii 

 general rule the ground color of a bird is the protective 

 color while many of the detailed markings are for 

 recognition. Warning colors (I. AiMsematic) are ap- 

 parently almost as rare in the bird world as the false 

 warning marks. The only genuine example with which 

 I am acquainted is to be found among the water birds. 

 It is the conspicuous white patch upon the head of the 

 tufted puffin {Lunda ciTrhda) which is very prominent 

 when the bird is upon its nest at the end of a burrow, 

 serving as a warning for intruders to avoid the sharp 

 and indeed dangerous beak which they are sure to 

 encounter.* 



The (II) Eplseinutic colors however, are very con- 

 spicuously represented among all classes of birds. These 

 are what are commonly known as recognition marks. 

 White, particularly in contrast to black, or some other 

 dark shade, is most frequently used for this purpose. 

 The markings of the wing and tail can doubtless be ex- 

 plained in this way in nearly every instance. It is 

 upon this class of markings that Wallace lays the greatest 

 stress, as accounting for a large proportion of the 

 diversity of markings and patterns in the bird world. 

 In explaining these markings he saysrf "If we con- 

 sider the habits and life-histories of those animals which 

 are more or less gregarious, comprising a large pro- 

 portion of the herbivora, some carnivora, and a con- 

 siderable number of all orders of birds, we shall see 

 that a means of ready recognition of its own kind, at a 

 distance or during rapid motion, in the dusk of twilight 

 or in partial cover, must be of the greatest advantage 

 and often lead to the preservation of life. Animals of 



' cf. Zoe iii, pp. 161-162. 

 t Darwinism, p. 217. 



