208 THE LIFE OF A BIRD. 



by what arrangement it is effected that the point 

 of life in the yolk is always kept uppermost, and 

 so nearest the fostering warmth of the parent's 

 heart. If we open a fresh egg, and turn it about 

 in every direction that is possible, so as to avoid 

 spilling its contents, it will invariably be found 

 that this life-point is at the top, so that no position 

 of the shell likely to occur in nature can cause its 

 place to be reversed, the little golden circle being 

 seen, however we may act with regard to the egg, 

 to be in the best place it could occupy for the 

 reception of vital warmth. There is no piece of 

 human mechanism with which it can be compared. 

 The accompanying diagram will furnish the best 

 explanation of this ar- 

 rangement. It will be 

 here seen that, attached 

 to the sides of the yolk- 

 bag, are two masses of 

 substance, which con- 

 sist, in reality, of thick- 

 ened albumen, and are called chalazce. Their 

 shape is somewhat pyramidal, and they are con- 

 nected to the yolk - bag by a number of 

 processes which attach them securely to its 



