ACQUIRED CHARACTERS 87 



mals where the distinction between the soma and the 

 germ is more sharply cut than among the lower ani- 

 mals and plants, yet, as Jennings points out, one meets 



FIG. 13. The behavior of an "acquired character," a spiny pro- 

 jection at one end of the body, in the case of Parameciwm. 

 The original individual is represented in the center and its 

 offspring, which arise by fission, are in successive circles. In 

 the fifth generation only one out of 32 shows the spine. 

 Data from Jennings. 



the same difficulties in the protozoa as in the metazoa. 

 The difficulty in the inheritance of acquired charac- 

 ters is not so much in separating germ and soma as in 

 the mechanism of cell-division. There seems to be no 

 way in which an acquisition located at one end of a 



