CHANGES IN THE EGG. 69 



than any only a few hours; it has even been stated 

 that in very warm weather the eggs of the meat- 

 fly will be hatched in about two hours ! In most 

 of these cases much depends upon the weather ; 

 but even this does not operate beyond certain 

 limits, for it has been said that in the month of 

 June, even if silk-worm's eggs were placed in 

 an ice-house, they would be hatched in spite of the 

 cold, but this observation deserves to be repeated. 

 It would be impossible to make the exact nature 

 of the changes which take place in the egg from 

 first to last easily understood in a work of this 

 kind. They have occupied the laborious in- 

 vestigation of talented observers with the highest 

 powers of the microscope, and although much is 

 now known on the subject, it is of a nature too 

 abstruse to be dwelt upon in our unpretending 

 volume. As we may well imagine, the changes 

 are wonderful indeed which from a little drop of 

 fluid matter, contained perhaps in a shell not 

 larger than a pin's head, end in the development 

 of the living and active larva, who makes his 

 speedy escape out of his shell-cradle. But they 

 must be studied in the scientific treatises which 

 are written upon this subject, and they are so 



