Weismann 285 



of several cilia, would then become transmitted only to 

 that one of the two new individuals to which the anterior 

 part falls in the division, and could in no wise be trans- 

 mitted to the other individual in which this anterior part 

 is formed anew. If one assumes on the contrary, that 

 transmission goes on by means of the nuclei, and can 

 therefore proceed equally into both of the two newly 

 forming individuals, one could not then understand, 

 wherein the transmission of somatic modifications in the 

 unicellular animals, which is accomplished by means of a 

 part of the organism containing in itself no membranelles 

 and quite distinct from them, would differ from the trans- 

 mission of any modification experienced by any organ of 

 a pluricellular organism, which likewise goes on by means 

 of a fragment containing no part of the modified organ 

 and quite distinct from it. So much the more since the 

 substantial identity of the complex unicellular with the 

 pluricellular organisms, which we have already discussed 

 above, corresponds also with a substantial identity in their 

 development, as is shown by the fact that the funda- 

 mental biogenetic law of the repetition of phylogeny by 

 ontogeny is followed in the development of unicellular 

 animals also, as for example, in the formation of the new 

 frontal field in the division of Stentor coereleus. 215 



And in relation to all these theories with preformistic 

 germs from Darwin to Weismann we might mention 

 once more the insurmountable difficulties that would be 

 encountered if one were required to explain by them this 

 very fundamental law, either in unicellular or pluricellu- 

 lar organisms. This impossibility and the fact that in the 



213 Johnson: A contribution to the Morphology and Biology of 

 the Stentors. Journ. of Morphol. ; vol. VIII, No. 3, Boston, U. S. A., 

 Ginn, August 1893. P. 519. 



