PROTOPLASM AND CHROMATIN 95 



contrasted with protoplasm, is its phosphorus content.^ It is 

 also distinguished by a strong affinity for certain stains which 

 cause its scattered or collected particles to appear intensely 

 dark (Fig. 13, A-E). Nuclein, which is probably identical with 

 chromatin, is a complex albuminoid substance rich in phos- 

 phorus. The chemical, or molecular and atomic, constitution 

 of chromatin infinitely exceeds in complexity that of any other 

 form of matter or energy known. As intimated above (pp. 6, 77), 

 it not improbably contains undetected chemical elements. Ex- 

 periments made by Oskar, Gunther, and Paula Hertwig (191 1- 

 19 1 4) resulted in the conclusion that in cells exposed to radium 

 rays the seat of injury is chiefly, if not exclusively, in the chro- 

 matin:- these experiments point also to the separate and dis- 

 tinct chemical constitution of the chromatin. 



The principle formulated by Cuvier, that the distinctive 

 property of life is the maintenance of the individual specific 

 form throughout the incessant changes of matter which occur 

 in the inflow and outflow of energy, acquires wider scope in 

 the law of the continuity of the germ-plasm (?'. c, chromatin) 

 announced by Weismann in 1883, for it is in the heredity- 

 chromatin^ that the ideal form is not only preserved, but 

 through subdivision carried into the germ-cells of all the 

 present and succeeding generations. 



It would appear, according to this interpretation, that the 

 continuity of life since it first appeared in Archaeozoic time is 

 the continuity of the physicochemical energies of the chroma- 

 tin; the development of the individual life is an unfolding of 

 the energies taken within the body under the directing agency 



^ Minchin, E. A., 1916, pp. 18,19. - Richards, A., 1915, p. 291. 



'The term " chromatin " or " heredity-chromatin " as here used is equivalent to the 

 " germ-plasm " of Weismann or the " stirp " of Galton. It is the visible centre of the 

 energy complex of heredity, the larger part of which is by its nature invisible. Chro- 

 matin, although within our microscopic vision, is to be conceived as a gross manifesta- 

 tion of the infinite energy complex of heredity, which is a cosmos in itself. 



