April 1892.] THE BOTANICAL SOCIETY OF EDINBURGH. 419 



imagine an egg feeding on a mass of waste products or 

 katastates, nor am I able to see how such katastates could 

 be the carriers of the tendencies of the male parent. Surely 

 only half-assimilated material, or partly, or entirely dis- 

 similated material, will never together form a new proto- 

 plasm, the bearer of the characteristics of both male and 

 female parent. Why further, should a katabolic male cell 

 *' get rid of all accessory nutritive material " ? — For the sake 

 of a change of diet ? 



Although I cannot agree with the authors in their views 

 as to the origin of sex and the interpretation to be given 

 to the phenomena of fertilisation, yet their " Evolution of 

 Sex " led me to my inquiry, and seems also to have led 

 Eyder and Hartog into an investigation of this highly 

 fascinating subject. Should my paper bring us a step nearer 

 the solution of this difficult problem I shall rest contented. 



Eyder, as we have already seen, considers sex to have 

 arisen as the result of " Cumulative integration," the zoospo- 

 rangia (spermatogonia) " either increasing enormously in size 

 to become ova, or running down, as a result of rapid kar- 

 yokinesis, into minute male elements, which are rapidly 

 •dehisced and set free." The most evident part of the egg 

 being the cytoplasm, and of the spermatozoon being the 

 nucleoplasm, the author concludes, p. 134, " that the origin 

 of sex at any rate hinges upon the decision of how the dis- 

 proportion between the chromatin and cytoplasm arose in 

 the sexual products of the two sexes," and that a restoration 

 of this disproportion between two cells has led to fertilis- 

 ation. 



"The male and female elements become reciprocally 

 attractive to one another (sometimes through the production 

 of certain chemical substances in the vicinity [Pfeffer.]), and 

 in that their idioplasm is less different from one another 

 than that of other cells, there is no bar to their fusion, which 

 is also favoured by the fact that in the male cell, with its 

 preponderant chromatin, there is now an attraction or need 

 developed for more cytoplasm similar to its own diminished 

 quantity, while conversely there is a similar need or attrac- 

 tion developed in the egg for additional chromatin, in con- 

 sequence of its preponderating cytoplasm. This leads to 

 the highest form of cumulative integration through direct 



