THE OYSTER. 65 



to feed the experimental claire, were completely ex- 

 empt." 



Such, briefly sketched, is the early history of the 

 oyster, and the process of rearing oysters artificially ; 

 but the development of the oyster is of vastly greater 

 interest than a mere description would indicate. It 

 contains enough material for philosophical meditation 

 and for scientific research to occupy many generations 

 of students. The practical importance of a knowledge 

 of its embryology does not end with the facts, for we 

 shall find among the deductions which naturalists have 

 drawn from it much that will help us to appreciate and 

 to utilize the oyster as food. 



When the egg is first laid it is a little globule of 

 living matter, with no visible indication of the struc- 

 ture of an oyster, although it is a potential oyster, and 

 is destined to build up, slowly, but surely, from the 

 vegetable food in the water, every part of a complicated 

 adult like that which produced it. It is not, however, 

 an oyster in miniature. Our utmost means of observ- 

 ation do not reveal in it anything whatever, at all like 

 the structure of the adult. Such structure as the 

 microscope does show is the structure of a cell, like 

 one of those which make up the oyster's body, and 

 the process of development is at first simply a process 

 of cell-multiplication, not the unfolding and enlarge- 

 ment of a rudimentary oyster. If we compare an 

 adult oyster to a brick house, then the egg corresponds 

 to a brick, not to a little house, and development begins 

 by cell-division or the multiplication of bricks rather 



