XI.] PROBLEMS OF THE DAY. 97 



inheritance of somatogenic variations. In these low plants the 

 difference between somatic and reproductive cells is slight, and 

 the body of the egg-cell does not require to undergo a complete 

 change in its chemical and structural characters in order to 

 develope into the body of the somatic cells of the daughter 

 individual. But what has this to do with the question whether, 

 for instance, the skill of a pianist's fingers, acquired through 

 practice, can be transmitted to his descendants ? How does 

 the result of this practice reach the germ-cells ? Here lies the 

 real problem which those who maintain the inheritance of 

 somatogenic characters must solve. 



The above-mentioned observations of Boveri on the ova of 

 Echinoderms deprived of their nuclei, prove that the body of 

 the egg-cell contributes nothing to inheritance. If then the 

 inheritance of somatogenic characters takes place, it can only 

 be by means of the nuclear substance of the germ-cells, that is 

 through the germ-plasm, and that not in its patent, but in its 

 latent state. 



To abandon the Lamarckian principle certainly does not 

 facilitate the explanation of phenomena, but what we need is 

 not a merely formal explanation of the origin of species, 

 although it may be the most convenient, but an attempt to 

 discover the real and genuine explanation. We must endeavour 

 to explain the phenomena without this principle, and I believe 

 I have made a beginning in this direction. I have lately 

 investigated the phenomena in a case where one would not 

 expect to be able to dispense with the principle of modification 

 through use, viz. in the case of artistic endowment \ I pro- 

 pounded to myself the question whether the musical faculty 

 in man could be conceived of as arising without the increase of 

 the original faculty by use. And I arrived at the conclusion 

 that not only was this principle unnecessary, but that use has 

 actually taken no share in the evolution of the musical sense. 



1 ' Gedanken uber Musik bei Thieren und beim Menschen.' Deutsche 

 Rundschau, October, 1889. Translated as the tenth essay,— the second 

 in the present volume. 



VOL. II. H 



