158 Animal Life and Intelligence. 



acquired by that particular group of protozoa whatever it 

 may be from which it originated. All future variations 

 in even the highest metazoa arise from these. 



Now, it is obvious that no mere commingling and re- 

 arrangement of protozoan characters could conceivably 

 give rise to the indefinitely more complex metazoan 

 characters. But if there be a combination and recom- 

 bination of these elements in ever-varying groups, the 

 possibilities are no longer limited. Let us suppose that 

 three simple protozoan characters were acquired. The 

 mere commixture of these three could not give much scope 

 for further variation. It would be like mixing carbon, 

 oxygen, and hydrogen in varying proportions. But let 

 them in some way combine, and you have, perhaps, such 

 varied possibilities as are open to chemical combinations 

 of oxygen, hydrogen, and carbon, whose name is legion, 

 but whose character is determined by the laws of chemical 

 combination. 



Summing up now the origin of variations, apart from 

 those which are merely individual, on the hypothesis that 

 particular modifications of the body-cells cannot be trans- 

 mitted to the germ-cells, we have 



1. In protozoa, the direct influence of the environment 

 and the induced development of faculty. 



2. In metazoa 



(a) Some direct and merely general influence of the 

 environment on the germ, including under the term " en- 

 vironment " the nutrition, etc., furnished by the body. 



(b) The combination and recombination of elementary 

 protoplasmic faculties (specific molecular groupings) ac- 

 quired by the protozoa. 



(c) Influences on the germ, the nature of which is at 

 present unknown. 



We may now pass on to consider the position of those 

 who give an affirmative answer to the question Can the 

 body affect the germ ? Two things are here required. 

 First, definite evidence of the fact that the body does so 



