604 PROFESSOR MARCUS HARTOG. 



With regard to the function of syngamy, taking the 

 widest sense of the word, the only general formula that will 

 cover the facts is that it effects a cellular reorganisa- 

 tion that can be effected in no other way. In many 

 cases it takes place between cells or nuclei related by tlie 

 closest bonds of cellular kinship, which is so much closer 

 than Metazoan kinship. Where, however, the gametes are 

 of different parentage, it undoubtedly, on the one hand, 

 tends to breed out individual deviations from the norm, as 

 Strasburger holds ; and, on the other, it produces new com- 

 binations of individual variations which offer wider fields for 

 natural selection, as Weismann postulates. Finally, I would 

 urge that no real advance can be made in any branch of 

 science as long as w^e use words without a precise meaning 

 attached to them ; and that we only hinder advance so long 

 as we base theories of the most wide-reaching significance on 

 facts obtained in a very limited field (sucli as, for instance, 

 the study of reproductive processes in the Metazoa), so long 

 as we use such theories as Procrustean beds on to which we 

 seek to make all other facts fit, whether by lopping them 

 where they prove too much, or by stretching them where 

 they prove too little. For these reasons, as a student of 

 plant and protistic life, as well as of that of animals, I am 

 grateful for the opportunity that my friend, the President, 

 has given me of addressing Section D on the subject of 

 fertilisation. 



Summary. 



1. The term fertilisation as actually used is too ambiguous 

 for scientific precision. 



2. In its first and older sense it denotes the starting into 

 active cell-life and multiplication of a resting-cell, and should 

 properly be regarded as one case of germination. The 

 parthenogenetic development of eggs under chemical and 

 mechanical treatment falls under this category. 



3. In its second sense, regarded now-a-days as the " strict" 



