THE FORMATION OF GERM-CELI.S 201 



suffered the same fate. This author states that 'as regards the 

 effect of fertilisation, it can only convert a 'portion of the eirir, 

 viz., the personal part, into the form of a person : the other 

 portion does not experience this effect, for it has a stronger 

 power of persistence." 



Finally, Nussbaum * was likewise led to the idea of the con- 

 tinuity of the germ-^<?/A\ He, too, assumed that • the segmented 

 ovum divides into the cell-material of the individual and the 

 cells for the preservation of the species,' and he supports this 

 statement by quoting the cases already mentioned of the very 

 early differentiation of the sexual cells. 



I will conclude this section with the words which appeared in 

 the preface to a short paper intended as a defence against the 

 accusation of plagiarism which had been made against me. 

 'A fertile scientific idea has rarely appeared without having 

 been contested on the one hand, and set down as already known 

 on the other. The former is certainly a perfectly justifiable and 

 even necessary course of proceeding, for a clear and definite knowl- 

 edge of the truth can only result from the contest of opinions : 

 and even the latter is to some extent justifiable, for an idea of 

 this kind probably very rarely arises without having been pre- 

 ceded by similar attempts directed towards the same object ; 

 and it is only natural that those who first made such attempts 

 should overlook the difference between these struggles towards 

 the desired object and its attainment." 



Others may decide the reason why no attention had been 

 drawn to the suggestions mentioned above as having been made 

 previously to my theory of the continuity of the germ-plasm, 

 and why these did not exert any influence on scientific thought. 

 This is certainly the case : and it practically follows from the 

 fact, that all the objections which have been made have been 

 directed against tne. Some of these objections will be discussed 

 in the following chapter. That I am far from desirous of de- 

 tracting from the merit of others, has, I trust, been shown by 

 the fact that as soon as I became aware of previous views on 

 the subject I brought them forward. Jager's ideas, for instance, 

 might have long remained unnoticed, had not I brought them 

 to light. But an historical account of the various previous views 



* M. Nussbaum, ' Die Differenzirung des Geschlechts im Thierreich,' 

 Archiv. f. mikr. Anatomie, Bd. xviii., 1880. 



