Examples of Warning Colouration 



smelling froth ; but this bear readily devoured 

 ordinary brown or green species. 



Among cold-blooded vertebrates the common 

 European salamander, with its bright black and 

 yellow markings, is a striking example of warning 

 colouration ; its skin exudes, on pressure, a very 

 poisonous secretion. 



Colonel A. Alcock has described a small 

 siluroid sea-fish, brightly banded with black and 

 yellow, and armed with poison spines. 



A well-known Indian poisonous snake, the 

 banded Krait (Bungarus cceruleus), is conspicu- 

 ously barred with wide bands of black and yellow ; 

 and in South America there occur numerous 

 species of coral snakes, in which red is added 

 to these conspicuous colours. 



The only known poisonous lizard the Helo- 

 derm of Mexico is conspicuously blotched with 

 black and salmon-colour. 



Among birds, no instances of warning coloura- 

 tion have been recorded, though Professor 

 Poulton has suggested that possibly the striking 

 and contrasted tints of many tropical species may 

 be due to this cause. The suggestion is an in- 

 genious one, but is at present totally unsupported 

 by evidence. 



The skunks are often cited as an excellent 

 example of warning colouration among mammals. 

 Skunks are most conspicuously arrayed in black 

 and white the latter above, not below, as is 



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