SEXUAL SELECTION 53 



33, B\ Mr. St. George Mivart informs me that it is not 

 furnished with muscles, and therefore cannot be used for 

 locomotion. As during the season of courtship it becomes 

 edged with bright colors, there can hardly be a doubt that 

 it is a masculine ornament. In many species the body 

 presents strongly contrasted, though lurid tints, and these 

 become more vivid during the breeding season. The male, 

 for instance of our common little newt (Triton punctatus), 

 is * brownish gray above, passing into yellow beneath, which 

 in the spring becomes a rich bright orange, marked every- 

 where with round dark spots.' The edge of the crest is 

 then tipped with bright red or violet. The female is usually 

 of a yellowish brown color with scattered brown dots, and 

 the lower surface is often quite plain." 



The males of some kinds of lizards have certain por- 

 tions of the body, especially about the head and neck, 

 brightly colored, and sometimes there are in these regions 

 brilliantly iridescent folds of skin which may be distended 

 and in this way made more showy (Plate 34). It is possible 

 that these are used in attracting the female. 



The mane of the lion, the antlers of the male deer, the 

 proud carriage of the male in many species of mammals, 

 may be instances of structures and habits used in courtship 

 and developed, in part, through sexual selection, though the 

 former two may be due partly to natural selection also, 

 since they are of use in fighting, the lion's mane as a pro- 

 tection, the deer's antlers as weapons. 



Referring once more to the birds, observe how the use 

 of these special characters and habits in the male is indi- 

 cated by the following facts (I quote from Romanes): 

 " (a) Male secondary sexual characters of an embellishing 



