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THE LIFE OF A BIRD. 



chick may be most pleasingly illustrated by a 

 little careful manipulation. Care must, however, 

 be taken to place only fresh-laid eggs in it which 

 in the metropolis it is not always easy to obtain. 

 After a period of eight or ten hours a change in the 

 appearance of the golden eye of the egg is discern- 

 ible by help of a lens. This change consists in 

 the appearance of a very delicate halo surrounding 

 this little spot. This halo continues to enlarge, 

 and at the end of thirty-six 

 hours it presents the singular 

 and beautiful appearance shown 

 in the cut. At this time the 

 heart, that is to say, the puls- 

 ating spot which forms its 

 earliest commencement, can be 

 seen beating and propelling 

 blood into the delicate vessels, 

 which now run over the yolk. 

 Some hours afterwards the form of the head, the 

 eyes, the beak, the spine, and several other parts 

 of the future chick are discernible. About the 

 third day rudiments of the wings and legs become 

 visible. At the fourth, or fifth, all those parts are 

 still more plainly discernible ; and it is a beautiful 



