CREATION BY EVOLUTION 



been formed (Fig. 3, B to F.). These five sets are like 

 different branches of a tree, all coming from one trunk. 

 They are separated by many generations from the original 

 parent A. During the passage of these generations the 

 different branches have become permanently diverse. Each 

 differs from the other hereditarily. Even when all are living 



A B C D 



Fig. 2. — Method of reproduction of Difflugia (after Verworn) . 



The parent A consists of a mass of protoplasm, covered by a rounded 

 shell made of sand grains cemented together. This shell has an enlarged 

 opening (below, in the figures). During its life the parent creeps about 

 at the bottom of pools. It takes up many sand grains, which it stores 

 within its body. At reproduction the protoplasm of the parent swells and 

 projects from the mouth of the shell A. This projecting part enlarges and 

 takes a form similar to that of its parent (at B and C). The nucleus of 

 the parent divides and one-half of it passes into the projecting portion. 

 The sand grains within the parent body also pass out into the projecting 

 mass, come to its surface, and spread over it (C and D). They are embedded 

 in a fluid secretion which now turns hard, forming a shell like that of the 

 parent. The two shells are in contact at their mouths. Now the mass of 

 protoplasm divides into two individuals, which separate, one retaining the 

 old shell (above in the figures) ; the other having the new shell. Later, each 

 individual repeats this process, producing another generation. 



under the same conditions the stocks remain diverse for gen- 

 eration after generation. From the original single stock 

 several hereditarily diverse stocks have been produced. Each 

 set or race included a large number of individuals, all shovv^- 



[28] 



