Stockakd: Nectar-glands of Vjcia Faba 257 



process of secretion ("the process of the discharge from cells of 

 their metabolic products "), but was active in the manufacture of 

 the secretion-substance, which process he termed " hylogcnesisy 

 I feel sure that in the case of the plant gland-cells which I have 

 studied this statement holds equally well. Since no Nebenkern or 

 fibers were found to exist in these cells, no direct morphological 

 relation could be established between the nucleus and the secre- 

 tion-product, although the staining reactions and the occurrence of 

 the granules lead one to think that the nucleus and particularly its 

 chromatic portion is active in the manufacture of the secretion- 

 products. Mathews further finds that during secretion the nucleus 

 moves from the base to the center of the cell, and during rest 

 it returns to a position at the base ; thus the nucleus in secretion is 

 passive, merely changing position, due possibly to currents in the 

 cell, but undergoing no structural changes. He states that he 

 finds no trace of a substance of any kind escaping from the nu- 

 cleus, nor did I observe any such phenomenon in the nectar-glands 

 under consideration. His final position may be seen in this quo- 

 tation : u I am, therefore, of Nussbaum's opinion, that the changes 

 in the nuclei of secreting cells are passive, and that the nucleus 

 plays no active part either in secretion or zymogenesis." 



Harrington ('99) found in the calciferous glands of the earth- 

 worm that the disintegration of cytoplasm is in direct ratio to the 

 amount of lime produced, and, as stated in my observations, as the 

 hair-cells become loaded with the secretion-product the cytoplasm 

 of the general gland-cells becomes much paler and therefore more 

 tenuous. At the height of constructive activity, when the cell is 

 ready for the changes which will^ result in the formation of lime 

 crystals, Harrington finds that the cytoplasm continues to increase 

 in extent, becomes less dense, and vacuoles appear-here and there, 

 the nucleus becomes decidedly vesicular, the nucleolus large and 

 densely staining. This description would apply to the cells figured 

 in most contributions on secretion, and in figure 16, which is a 

 gland at the height of secretion, these structures are to be seen. 



Schniewind-Thies ('97) studied the nectar-glands in a large 

 number of plants and found that the nuclei of secretion-surfaces 

 are everywhere distinguished from those of the parenchyma by 

 their greater contents of chromatin. She found in secreting cells 



