10 BRITISH BIRDS* EGGS. 



days the pupil of the eye,, indications of the lungs, and the 

 spinal marrow may be observed ; on the ninth and tenth days 

 the bones begin to form, and the muscles of the wings, with 

 the germs of feathers, appear ; and thus the growth pro- 

 ceeds till some three weeks or more may have elapsed, when 

 the bir.d, sufficiently matured, escapes from the shell and 

 enters upon the more active functions of its life. Contrary 

 to an opinion perhaps extensively prevailing, the young are 

 not aided by the parent bird in escaping from the shell, 

 but are supplied with a hard projection on the upper man- 

 dible, near the tip> with which, it is believed, they are en- 

 abled to break the shell, and thus escape ; and it is remark- 

 able that shortly after the young are hatched, this horny 

 point separates from the bill and falls off. 



A gentleman to whose kindness, as already acknowledged, 

 we are indebted for many of the subjects which illustrate 

 this volume, and whose habits of accurate observation give 

 value to his remarks, thus writes to us: " I have* examined 

 many hundreds " of eggs. " The operation of leaving the 

 shell is a very beautiful one, and exhibits very markedly 

 the wisdom and contrivance of the Creator. The beak is 

 furnished with a horny point, which afterwards drops off: 

 this is protruded through the shell : by means of its feet as 



