Skin Changes. 1 1 1 



Not only in feathers, however, does the bird 

 express his masculine activity. He sometimes 

 wears a stately comb and gorgeous wattles, and his 

 legs are armed with martial spurs, which he has no 

 doubt encouraged to their formidable proportions 

 by the exercise of another masculine character- 

 istic, the desire to kick out of the way his 

 rivals. 



In some species the bird wears his livery all the 

 time; in others, however, the finest plumes appear 

 as a special ornament at the season of love, and the 

 discreet female is said to select the knight of the 

 gayest attire as the father of future generations, 

 thus developing and preserving beauty on the 

 earth. 



Dewlaps in cattle, skin folds and excrescences 

 in other mammals, illustrate abnormal skin-growths 

 in the higher animals. 



Among insects, the ovipositor, with its formidable 

 armory of saw, file, auger, sting, the complicated 

 intromittent organ, are skin outgrowths, and are 

 generally the product of the imago or sexually 

 mature condition. 



Even the wings of insects are a result of the 

 power to vary displayed by the skin, for from skin 

 folds come forth these brilliant gossamers. 



Feathers, scales, spines, hair, are closely related 

 outgrowths of the skin, and many males express 

 their masculine vitality in unusual growths of hair 

 at the time of reproductive maturity. The male 



