SELECTION 173 



mann suggested that the concepts of " strug- 

 gle" and "selection" might be usefully 

 extended to the individual items which com- 

 pose the germ-plasm, or, what comes to the 

 same thing, the inheritance. If we suppose, 

 as there are many reasons for supposing, that 

 the physical basis of inheritance in the germ- 

 cells is composed of a multitude of repre- 

 sentative vital particles which are able to 

 feed, grow, and multiply, then it is con- 

 ceivable that fluctuations in the nutritive 

 supply of the germ-cells, and inequalities 

 in the vigour and assimilating power of the 

 hereditary constituents, may result in an 

 intra-germinal struggle and selection. 



The general idea is a familiar one, that 

 nothing succeeds like success; and vice 

 versa. A strengthened representative item 

 or determinant in the germ-plasm will nour- 

 ish itself more abundantly than its neigh- 

 bours. "It may get into a permanent up- 

 ward movement, and attain a degree from 

 which there is no falling back." On the 

 other hand, a weakened determinant will 

 have less power of attracting nutriment, and 

 will tend to go downhill. If it be the deter- 

 minant of something useful, then the ordinary 

 process of natural selection will eliminate 

 the individual that develops from the im- 

 poverished germ-cell; if it be the determi- 



