CHAPTER XX 



THE COVERINGS OF YOUNG BIRDS 



THE consideration of birds' eggs has long been popular, though now 

 the tendency is rather for nature students to preserve pictures of 

 nests and their contents than to " take " them to form a collection. 

 A deal of discussion has taken place with regard to the meanings 

 of the colours of eggs, but quite as much interest surrounds the 

 appearance of newly hatched birds and the rapid changes that take 

 place in it. A great amount of new work might be done in the 

 direction of showing how far and in what cases the coloration of 

 young birds is protective. There are of course familiar instances 

 of young birds which do not remain in the nest or lie in an apology 

 for one, that are practically invisible unless they move, but little 

 observation has been brought to bear upon nestlings. 



The black down which is to be seen on young robins (figures 

 135-138), forming the frontispiece of Part II) is most striking, and 

 the feathers, mottled with yellowish markings, which replace it, differ 

 greatly from those of the adult bird. There are of course many 

 possibilities of the colouring of nestlings being similar to that 

 of their remote ancestors as are the spots on young lions or tapirs 

 and the stripes on the young of the wild boar. 



We may distinguish birds which are hatched completely covered 

 with down and able to run about to feed themselves as soon as 



23 



