SELECTION 143 



district will hold and they are those in which all 

 necessary characters are combined. If leaping was 

 important, those animals would have the advantage 

 in which the combination of characters favourable 

 for leaping was most pronounced. A single defect 

 of any kind would be fatal. 



Natural selection has no particular tendency to 

 preserve individuals with one beneficial character 

 only ; but selects those which possess the best col- 

 lective qualities for success in the struggle for exis- 

 tence. The struggle is generally continuous, and 

 not intermittent, as is- so often supposed. Droughts 

 and famines may occur occasionally, but their 

 effects are soon obliterated by a succession of good 

 seasons. It is the ordinary, not the exceptional, 

 season which determines the action of natural 

 selection. 



Nevertheless, the occurrence of the right varia- 

 tions at the right places, at the right times, and in 

 many succeeding generations, is certainly very re- 

 markable, and seems to require definite variation to 

 explain it. This explanation was attempted by 

 Weismann in his hypothesis of germinal-selection. 

 But that only shews why a character once selected 

 would be likely to reappear in a still more modified 

 form in succeeding generations ; it does not touch 

 the question of the simultaneous origin of several 

 variations. A better explanation is found in Pro- 

 fessor Bering's theory ; for any organ which was 

 specially useful would be much used, and this would 

 be re-echoed by the germ, and in the next genera- 

 tion all the useful organs would be better developed. 



