no THE INFANCY OF ANIMALS 



of coloured areas and markings not as a rule found in 

 the adult stages. 



Let us begin with the account of the ornaments. Our 

 first case shall be that of the nestling of the common coot 

 {Fulica atra). In this bird, it may be remembered, the 

 downy covering is black, and this is set off, during the 

 first few days of nestling life, by the development of 

 vermilion and yellow hues on the head. The vermilion 

 area is formed by numerous minute, fleshy outgrowths 

 or vilU, which have a velvety appearance, and exactly 

 resemble the villi which form the vermilion face wattle 

 of the pheasant. The yellow is borne by long thread-like 

 down feathers. But there is at this stage no sign of the 

 white shield of bare skin on the forehead so conspicuous 

 in the adult. 



In the nestling waterhen, on the other hand, the beak is 

 of a bright red, and there is a trace of the frontal shield, 

 also bright red in colour, as in the adult. Later, when in 

 its first plumage of true feathers, the red gives place to 

 a dull brownish green, and this in due course once more 

 gives place to vermilion. In the nestling of the great 

 crested grebe the crown of the head is ornamented by a 

 heart-shaped shield of bare skin, vermilion red in hue : 

 yet no such ornament is present in the adult, in which 

 the crown is covered with feathers. 



Has this curious patch any special significance ? Per- 

 chance it is a recognition mark, enabling the parents to find 

 the young after they have dispersed into hiding to avoid 

 an enemy. If this be so it is difficult to see why a similar 

 mark should not have been developed by other species of 

 young grebes : yet such is not known to be the case. Never- 

 theless, it is significant that young grebes, coots, and water- 

 hens all agree in this display of red at this stage of existence. 



