38 THE EVOLUTION OF CONTINUITY 



attraction, and is continued through many acts of plasmole- 

 cular repulsion or division till the original plasmolecular 

 plans are restored in the sexual elements. This supposition 

 does not seem unreasonable in view of the undoubted fact 

 that the growth-cycles of living Individuals begin with the 

 attraction of sexual elements, and are continued through 

 many acts of cell-division (repulsion) till the elements are 

 reproduced. Admittedly, it entails the acceptance of the 

 living protoplast as essentially a multiple of plasmolecules, 

 and makes cell-division the immediate sequence of plas- 

 molecular division. 



As in cellularly continuous organisms the main road of 

 evolution leading to sexual-element reproduction gives off 

 many side-roads ending in the fixed tissue cells, so one may 

 believe that in the cell, which is on the whole a molecularly 

 continuous organism, the main road of plasmolecular evolu- 

 tion gives off side-roads leading to the differentiation of 

 fixed substances — the " somatic substances " of the cell. 



The Individual. 



Before going farther it is necessary to define exactly 

 what an " Individual " is, as the term will be constantly 

 used, and always within the limits of the definition. 



Every independent living entity is not an Individual in 

 the scientific sense of the term. Far from it. For example, 

 a single aphis or greenfly is never one, nor is a queen bee, 

 nor a drone. On the other hand, a worker bee always is, 

 with rare exceptions. One rosebush may be a developing 

 Individual, while another may not be. A malarial amoeba 

 can never become an Individual, and no more can an 

 independent alga cell. 



A living Individual may be defined as the Sum oe a 

 Complete Growth-cycle, from its beginning up to where 

 it finishes with the full possible reproduction of the originally 

 combining elements. 



Two things follow from this. First, when the Individual 

 cycle runs through many organisms, unicellular or multi- 

 cellular, which enjoy a free and independent existenoe, as 



