The Bird in the Egg 



463 



and the presence of water in the other, will slowly take 

 on the semblance of living creatures; the one eventually 

 to swim forth, live the life of a fish for a time, then to 

 leap upon the land and croak among the reeds. The 

 other yolk would have evolved into a downy, yellow chick. 

 We cannot hope to solve the mystery of life, but there 

 is a fascination in seeing how near its beginnings we can 

 approach. 



Fig. 364. — Egg of Hen, opened to show a 3-day embryo in position on the yolk. 



(Slightly enlarged.) 



If we have ever watched under the microscope the strange 

 little creatures which live in the mud at the bottom of 

 ponds, we will have realized the wonderful possibilities of a 

 single drop of living matter, — a single cell, — from the 

 amoeba with its ever-changing shape to the swiftly moving 

 slipper paiamecium and the beautiful animal vases, — the 



