178 COMPARATIVE ANATOMY 



Color in Races and Individuals. The blue of the iris of human children 

 and new-born kittens is an interference color, like the blue of the sky or 

 the eyes of a peacock's tail. Later, as the iris fibers thicken, the inter- 

 ference is less perfect, and the eye is gray. Brown pigment in some fibers 

 only, gives hazel. Brown eyes are evenly pigmented. Dark brown eyes 

 are called black. 



There is also the yellow pigment, which, nearly free from brown, gives 

 the amber eyes of some blondes. The same color intensified, makes the 

 red iris that sometimes accompanies red hair. The interference blue 

 slightly masked by yellow, gives that rarest of all eye colors, green. 



In general, among Europeans, the eyes are less pigmented than the 

 hair, so that dark hair with gray-blue eyes is common. But some blondes 

 have a striking color scheme, eyes darker than the hair. 



Hair is colored by the same two pigments, both usually present, with 

 the brown-black, masking the red-yellow, except in strong light. But 

 some dark hair lacks the red and is blue-black. 



Some blondes have no brown pigment, and little yellow. Most have 

 brown also, along with varying amounts of yellow. The tow head with 

 a touch of dark, is the ash blond. Yellow with some red is golden; and 

 starting from this, the red may strengthen to a rather unadmired carrot 

 or orange. More brown carries the red over into auburn; still more gives 

 bronze. 



Hair that has lost its color is white, for the same reason that snow is, 

 the crystal faces of the one and the cell walls of the other scatter the 

 light. 



Skin color is like hair color except that the blood color below the 

 pigment may show through, and that sunHght, which fades the lifeless 

 hair, stimulates the living skin to turn dark. 



Primitive man was dark as the ape ancestor was, and as most races 

 are still. Reducing the black pigment with the yellow retained, gives 

 the Mongolian skin color. The stronger yellow, together with a good 

 deal of brown, is the traditional hue of the Red Man, though as a matter 

 of fact, most Indians are brown, like most White Men. 



The blond White Man is a local race that originated in some region 

 near the Baltic, apparently since the last Ice Age. Being highly energetic 

 and uncommonly well endowed, the descendents of these blond giants 

 have made their way all over the world, and, much diluted with darker 

 blood, still appear in most civilized countries of the world. 



Why their blondness, nobody knows. It cannot be due to climate, 

 for the Eskimos, Samoyads of Siberia, the Patagonians, and the people 

 of northern China are all dark. Naturally, a blond race could hardly 

 survive in the tropics; but a white skin is no obvious advantage anywhere. 

 Yet certain studies of Chicago children show that the highly pigmented 



