THE OYSTER. 67 



go, they reveal nothing whatever in the egg which 

 resembles the adult in any particular, nor do they 

 show anything in the oyster egg which should cause 

 it to become an oyster rather than some other animal. 

 The testimony of all observers, based upon the study 

 of all kinds of animals, is that the egg is not compara- 

 ble to the adult in miniature, but to one of the con- 

 stituent cells of its body; that the development of an 

 egg is not the unfolding of a germ, but a process of 

 cell-multiplication. The egg divides into a number of 

 cells like itself, and these divide and subdivide until 

 they are very numerous. At first they are alike, but 

 they soon become specialized in different directions, 

 and thus gradually build up the tissues and organs of 

 the body. These gradually acquire their final form, 

 but they are at first simple cell-aggregates, out of 

 which the complex whole is finally built up by the 

 combination and organization of the simple units, some- 

 what as a regiment of soldiers is organized from a 

 mob of men. 



The directing influence must be in the egg, although 

 it has so far eluded all efforts to discover it. The adult 

 oyster, with its complicated organs, so beautifully and 

 wonderfully fitted to its needs, and so intricately re- 

 lated to each other as parts of a complex whole, is a 

 most interesting subject for study. No one can study 

 the structure of any animal without admiring the fit- 

 ness of all its parts for their work. As we trace out 

 the use of one part after another, and the oyster be- 

 comes intelligible to us, its completeness impresses us 



