SPECULATIONS UPON THE ORIGIN OF LIFE 643 



It is therefore probable, if not certain, that chondriosomes 

 and perhaps other constituents of the cytoplasm play an 

 important part in the transmission of hereditary characters. 

 I do not for a moment mean to imply that the part played by 

 the chromosomes is not an important one. The point I wish 

 to make is that, at the present time, in view of recent work, no 

 one has any right to make the exclusive claims for them that 

 were considered justifiable in the past and which are still con- 

 sidered valid by perhaps the majority of biologists. I have 

 elsewhere given the details of a possible interpretation of the 

 relative parts played by the chromosomes and other portions of 

 the cell with regard to the transmission of hereditary characters ; 

 or, to speak more correctly, of the potentiality for developing 

 these characters. 1 Here I only wish to show that this function 

 cannot possibly be confined to the chromatin. 



The next point is the relative importance of nucleus and 

 cytoplasm. Here the very general opinion of biologists is that 

 the nucleus is of supreme importance, the cytoplasm playing but 

 a subsidiary part. With this opinion I am again at variance. 

 The nucleus qua nucleus is of no more importance than the 

 cytoplasm. Prof. Minchin says that a portion of cytoplasm 

 without nucleus cannot survive. Quite so, but it also seems 

 that neither can a portion of nucleus survive without cytoplasm. 

 Verworn, whose experiments upon the protozoa with regard to 

 this point are among the most important, 2 came to the conclusion 

 that the one was as important as the other; neither could survive 

 alone, whilst from a small piece of nucleus together with a small 

 piece of cytoplasm a whole organism might be formed. 



Much stress is laid upon the fact that in some cells, notably 

 sperms, the nucleus and its contained chromatin form so large 

 a part of the whole ; it is therefore concluded that the cytoplasm 

 is of little or no importance. In view of the facts I have already 

 adduced, I feel that the actual relative volumes of nucleus and 

 cytoplasm are not of fundamental importance with regard to 

 the subject under discussion. The nuclei of ova are as small 

 relatively to the whole cell as those of sperms are large. The 

 cytoplasm of the ovum has, of course, to provide nourishment 

 during a greater or less period of time after fertilisation and 



1 Walker, C. E., " Hereditary Characters " (Arnold, London, 1910). 

 s Verworn, M., "Die physiologische Bedeutung des ZellkernS)" Archiv fiir 

 die qcsammte Physioloqie, ii. 1891. 



