No. 533] NUCLEUS AM) CYTOPLASM IX H KUKD1TY 289 



the basic-staining food-stream as the result apparently 

 of the discharge of oxidase from the nucleus into the 

 cytoplasm of the egg. Again, it is of great significance 

 that in the embryos of seeds the time of greatest fer- 

 mentative activity in starches and other fermentable 

 bodies coincides with that of maximum size of the nuclei. 

 Many other significant facts might be adduced, but I wish 

 merely to show that there is abudant evidence pointing 

 to the nuclei of cells as sources of enzymes. 



The idea that among other things the nucleus is con- 

 cerned with enzymic activities in the cell, or, indeed, that 

 the chromosomes themselves are sources of ferments, is 

 by no means a new one. The last few years has seen a 

 steadily increasing tendency to regard them as such. The 

 latest and most outspoken suggestion of this nature, of 

 which I am aware, is the argument that Montgomery," 

 brings forward in a recent paper. He says in part. "The 

 relative constancy of chromatin mass in spermatocytes 

 and spermatids of very different volumes speak strongly 

 for its enzyme nature." Then after pointing out the rel- 

 ative constancy in size between the univalent components 

 of spermatogonia and spermatocytes in Euschistis and 

 reminding us of the well-known fact that, although the 

 egg is many times greater than the sperm, the chromo- 

 somal contribution of each is the same in size and mass, 

 he goes on to say that, "An enzyme possesses among 

 other properties the power of engendering changes in its 

 medium while still preserving a constant mass. ' ' And he 

 continues, "Of all the larger cellular compounds that we 

 know, the chromosomes agree most closely with this defi- 

 nition, and by reason of this constancy of mass alone 

 might be considered enzyme masses." 



My present thesis, however, while in harmony with all 

 this, is yet different. It is rather just the complement of 

 such a proposition as Montgomery's for it is an attempt 

 to show reasons why there must be a nicely adjusted 

 series of such substances in the germ-cells as enzymes. 



In any epigenetic conception of the germ-cell — and this 



'Biol. Bui., Vol. XIX. pp. 1-17, 1910. 



