6 THE RISE OF MAN. 



Auswickelung, i. e., unfoldment (literally, "outrolling") 

 a theory of development from within, the other u epi- 

 genesis," or the theory of development by additional 

 growth from without. According to the theory of evolu- 

 tion, the nature of the higher animals was assumed to be 

 predetermined by the mysterious disposition of their orig- 

 inal life-plasma, in about the same way as the chicken, 

 with all its limbs, its bodily and psychic faculties, is some- 

 how pre-existent in the ovule of the egg. However, ac- 

 cording to the epigenesis theory, new properties are 

 acquired by experience, and thus it would appear that 

 external conditions determine the further development of 

 life. The term Devolution" was used in those days in 

 its original meaning of something being unfolded (rolled 

 out) from a latent state into a visible and plainly percep- 

 tible form, but since Darwin's time, we use the word in 

 place of u epigenesis "; for the theory of epigenesis has 

 practically been established on the basis of observation 

 and experiment, and the Germans speak no longer of 

 Auswickelung, but of Entwickelung. The majority of 

 naturalists of this age hold that growth of the higher life 

 is not directly due to the latent qualities of ancestors, but 

 is the result of new acquirements conditioned by extended 

 experiences under definitely given surroundings. The 

 progress which mankind is making still in its onward 

 march to the higher planes of existence, is due to the les- 

 sons of life and not to the mysterious potencies of pri- 

 mordial germs. 



The chicken's egg is different from the primordial 

 life-plasma. Its ovule contains in the latent form of dis- 

 positions the experiences of all its ancestors a kind of 

 race-memory which will reproduce the chick type by evo- 

 lution in the original sense of the term. 1 



1 This statement is subject to certain restrictions which we do not care to dis- 

 cuss in detail in this connection. The ovule contains the memories of the chick- 

 race, but its growth takes place by repeating the process of epigenesis. 



The egg does not contain feathers, or eyes, or a bill, or feet, but certain life- 



