THE OYSTER. 63 



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

 they soon become specialized in different diiections, 

 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, 

 somewhat 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 

 more and more; but if we are thus impressed by the 

 study of a complicated mechanism, adapted for bring- 

 ing about complicated results, what must be our re- 

 flections when we find in the ^^^ the capacity for pro- 

 ducing the same results without any visible mechanism 

 whatever! Everything which seems so admirable in 

 the adult, when it is the result of organization, exists 

 potentially in the ^^^^ where there is no discoverable 

 organization ; and if the result of the process of de- 

 velopment, the complete oyster, is wonderful and in- 

 teresting, how much more wonderful is the process 

 itself. To those who can picture in imagination its 

 hidden structure, an ^^^ is one of the most marvel- 



