JoLY — The Abundance of Life. 73 



events would ultimately become hereditary may, I think, be under- 

 stood when we consider in what way they recurrently affect the 

 successive reproducing organisms. The older members of the race 

 continuing to reproduce themselves, and at the same time experienc- 

 ing the increasing effects of want, and possibly of the attacks of 

 the younger, will produce ever more feeble offspring, till the weak- 

 ness becomes congenital, or, in other words, tlie germ cells ultimately 

 responding to the effects of the restricted nourishment, evolve beings 

 capable of but a limited span of life. Similarly the phenomena of 

 old age will become :inherent in the race, and subsequently will 

 appear in the individual living under the most favourable condi- 

 tions of supply. 



It will be urged, perhaps, that there cannot be much difference 

 in specialisation between the old who perish and the young who 

 survive. It must be remembered, however, that a small thing will 

 affect the result. A germ-tendency to longevity, resulting in 

 abnormally old individuals, will be the more sternly met according 

 as it tends to prevail. If these exceptional organisms reproduce 

 themselves more abundantly they will have more abundant foes, 

 and, by heredity, probably stronger foes to contend against. Slight 

 differences in endurance, in fleetness, or in cunning, etc., will in 

 the long run act powerfully in adjusting the time-limit of the 

 individual. In fact the older individual has a majority of better 

 specialised individuals to contend against, and even where the sup- 

 plies of the environment are sufficiently abundant for all, yet in the 

 crowd would have a bad chance of continued survival. 



In the case of reproduction by subdivision, where this is im- 

 partial, there is a sharing of advantageous properties among the 

 derived units ; until some particular line of descent is favoured by 

 chance of locality, all remain equally equipped in the struggle for 

 the mastery. Nor would there in any case be progressive periodic 

 destruction of older units by younger ; for, indeed all may be con- 

 sidered of the same age. And so, in fact, among the unicellular 

 organisms, which display little or no adaptation, no period of 

 death is assigned to the individual, and, as observed before, it 

 averts the effects of overgrowth by its subdivision. 



To organisms in this state of equilibrium we must refer for the 

 inherent dynamic attitude of life ; and, as we see, it is undoubtedly 

 one of progress. It is true that, philosophically, we may regard 



