BIRD NESTING. 117 



of these. And so, when the guests are in at luncheon they are 

 sometimes entertained by the sight of a small box brought in, in 

 which a Blue Tit is sitting on its eggs. The cover is removed, the 

 bird is exposed to full view, it is passed round from one to the 

 other, yet there it sits on, undaunted, only watching with bright 

 eyes, and trusting things are well and chivalrous. 



There are few problems more interesting, but few, it seems, 

 more impossible to solve, than the reasons for the colourings of 

 ^ggs- Take the case of hidden eggs — eggs down in the dark, in 

 holes of hollow trees. We say they want no colour here, and that 

 this is why the Woodpeckers and Owls lay eggs that are pure white. 

 And this is well enough as a reason, until we are met on the one 

 hand by such a case as that of the Redstart, whose egg is sky-blue, 

 or, on the other, by that of the Wood-pigeon, whose egg is white. 

 With which conundrum we will stop. 



