244 THE GENESIS OF SPECIES. [CHAP. 



it is only reasonable to attribute such to each individual 

 organism. 



The conception of such internal and latent capabilities 

 is somewhat like that of Mr. Galton, before mentioned, ac- 

 cording to which the organic world consists of entities, 

 each of which is, as it were, a spheroid with many facets 

 on its surface, upon one of which it reposes in stable equi- 

 librium. When by the accumulated action of incident 

 forces this equilibrium is disturbed, the spheroid is sup- 

 posed to turn over until it settles on an adjacent facet once 

 more in stable equilibrium. 



The internal tendency of an organism to certain consid- 

 erable and definite changes would correspond to the facets 

 on the surface of the spheroid. 



It may be objected that we have no knowledge as to 

 how terrestrial, cosmical, and other forces, can affect organ- 

 isms so as to stimulate and evolve these latent, merely po- 

 tential forms. But we have had evidence that such myste- 

 rious agencies do affect organisms in ways as yet inexpli- 

 cable, in the very remarkable effects of geographical condi- 

 tions which were detailed in the third chapter. 



It is quite conceivable that the material organic world 

 may be so constituted that the simultaneous action upon it 

 of all known forces, mechanical, physical, chemical, mag- 

 netic, terrestrial, and cosmical, together with other as yet 

 unknown forces which probably exist, may result in changes 

 which are harmonious and symmetrical, just as the internal 

 nature of vibrating plates causes particles of sand scattered 

 over them to assume definite and symmetrical figures when 

 made to oscillate in different ways by the bow of a violin 

 being drawn along their edges. The results of these com- 

 bined internal powers and external influences might be rep- 

 resented under the symbol of complex series of vibrations 

 (analogous to those of sound or light) forming a most com- 

 plex harmony or a display of most varied colors. In such 



