CELL-LIFE AND CELL-MULTIPLICATION. 265 



tntos the head of the spermatozoon, and in plants that of the 

 spermatozoid or antherozoid, is distinguished from the other 

 agents concerned by having the highest proportion of the 

 phosphorized element; and it also harmonizes with the fact 

 that the extremely active changes set up by fertilization are 

 accompanied by decrease of this phosphorized element. Spe- 

 culation aside, however, we may say that the two functions of 

 the chromatin do not exclude one another, but that the general 

 activity which originates from it may be but a lower phase 

 of that special activity caused by fertilization.* 



§ 74(7. Here we come unawares to the remaining topic em- 

 braced under the title Cell-Life and Cell-Multiplication. We 

 pass naturally from asexual mutiplication of cells to sexual 



* The writing of the above section reminded me of certain allied views 

 which I ventured to suggest nearly 50 years ago. They are contained in 

 the Wcsimi7ister Revieto for April, 1852, in an article entitled "A Theory 

 of Population deduced from the General Law of Animal Fertility." It is 

 there suggested that the " spermatozoon is essentially a neural element, and 

 the ovum essentially a haemal element," or, as otherwise stated, that the 

 *' sperm-cell is co-ordinating matter and the germ-cell matter to be co ordi- 

 nated " (pp. 490-493). And along with this proposition there is given some 

 chemical evidence tending to support it. Now if, in place of " neural " and 

 "haemal," we say — the element that is most highly phosphorized and the 

 element that is phosphorized in a much smaller degree ; or if, in place of 

 co-ordinating matter and matter to be co-ordinated, we say — the matter 

 which initiates action and the matter which is made to act; there is dis- 

 closed a kinship between this early view and the view just set forth. In the 

 last part of this work, " Laws of Multiplication," which is developed from the 

 essay referred to, I left out the portion containing the quoted sentences, and 

 the evidence supporting the conclusion drawn. Partly I omitted them because 

 the speculation did not form an essential link in the general argument, and 

 partly because I did not see how the suggested interpretation could hold of 

 plants as well as of animals. If, however, the alleged greater staining capac- 

 ity of the male generative nucleus in plants implies, as in other cases, that the 

 male cell has a larger proportion of the phosphorized matter than the other 

 elements concerned, then the difficulty disappears. 



As, along with the idea just named, the dropped portion of the original 

 essay contains other ideas which seem to me worth preserving, I have thought 

 it as w ell to reproduce it, in company with the chief part of the general argu- 

 ment as at first sketched out. It will be found in Appendix A to this volume. 



