CHAPTER III 

 WEISMANN'S THEORY OF THE GERM-PLASM 



jo. The Significance of the Cell-Pedigree for the Doc- 

 trine of the Germ-Plasm 



In the first two chapters of this section I have compre- 

 hensively described the cell-pedigrees for the plant world, 

 and, in order to draw a clear picture, I have been com- 

 pelled to introduce a number of new names. The fact that 

 all the cells of the whole plant-body are produced by 

 division, is now universally recognized, and herewith the 

 possibility of the establishment of cell-pedigrees is admit- 

 ted as a matter of course. Furthermore, the scientific 

 value of such consideration has been pointed out by dif- 

 ferent investigators in botany as well as in zoology. 



The elaboration of the picture, however, as I men- 

 tioned in the beginning of this division of Part II, seemed 

 indispensable to me, because, up to the present time, the 

 higher animals have been put to the front in these consid- 

 erations, and for the further reason that this fact leads 

 only too readily to a one-sided conception. For here the 

 distinction between the germ-cells and the body-elements 

 is so great that it only too easily gives the impression of a 

 qualitative difference. 



This contrast has been strongly emphasized by Weis- 

 mann in his interesting speculations on the "mortal" so- 

 matic cells and the "immortal" germ-cells, 22 and forms, to 

 a large extent, the basis for his theory of the germ-plasm. 



22 Weismann, A. Ueber die Dauer des Lebens. 1882. Ueber Leben 

 und Tod. 1884. 



