170 Gardner — Studies on Grcr^Jth and Cell 



direct connection with the nutritive substance and forces 

 of the nucleus. 



Next Strasburger's views will be given as taken from his 

 paper " Ueber Cytoplasmastructuren, Kern und Zelltliei- 

 lung." 



In pollen mother cells of Larix, in preparations stained with 

 saffranin and gentian orange, Strasburger observed that at first 

 the kinoplasm was stained violet, but that this violet color 

 disappeared simultaneously with the aggregation of the 

 nucleolar substance in the nucleus. This suggested that the 

 nucleolar substance stood in relation with the activity of the 

 kinoplasm. These observations were confirmed by the inter- 

 nal relations which the nuclei in Fucus, Sphaeroplea, and the 

 asci of the Ascomycetes showed to the formation of the aster. 

 Between the nucleus and kinoplasm exists, therefore, a close 

 relationship, and on these observations he founds the view that 

 the nucleolar substance represents a reserve material, from 

 which the kinoplasm derives its activity. R. Hertwig's 

 observations show the relations which exist between nucleolar 

 substance and the chromosomes — for he saw that the nucleolus 

 disappeared as the chromosomes became distinct. 



Professor J. M. Macfarlane, in a paper, " The Structure of 

 Plant Hybrids and Parents," gives the following, which is a 

 concise statement of his views, clearly stating the position 

 taken by him : 



" The nucleolus is the special chromatic and cell center. It 

 forms the main mass of chromatin substance, and is connected 

 by an extremel)' fine network system with the nuclear mem- 

 brane which is also chromatic, and during division breaks 

 down to fuse with the radiating threads from the nucleolus. 

 In the reformation of the daughter nuclei also, round the 

 nucleoli the nuclear membrane reappears first on the outer 

 pole or nuclear face, but some can be traced to the pyrenoid 

 centers." 



