202 Pang ens in the Nucleus and Cytoplasm 



sis, one does not arrive at a satisfactory view of the re- 

 lation between nucleus and cytoplasm. 



If my hypothesis is rejected and the prevailing con- 

 ception concerning the contrast between nucleus and cyto- 

 plasm is followed, we can imagine the effect of the 

 nucleus to be either dynamic or enzymatic. 



Strasburger represents the first view. According to 

 him, the reciprocal action between the nucleus and the 

 cytoplasm is a dynamic one, meaning that it takes place 

 without transmission of substance.^ For this investigator 

 has never been able to discover, in his extensive studies, 

 a transmission of visible particles. *'From the nucleus, 

 molecular excitations are transmitted to the surrounding 

 cytoplasm which dominate, on the one hand, the processes 

 of metabolism in the cell, and on the other hand, give a 

 definite character, peculiar to the species, to the growth 

 of the cytoplasm, which depends on nutrition." As long 

 as it is a question of general insight only, this assumption 

 is sufficient, but as soon as attention is directed to indi- 

 vidual processes, we meet with insurmountable difficulties. 

 Morphological phenomena are indeed far from having 

 been sufficiently analyzed to allow a true understanding, 

 but in the meantime we can turn to the much simpler 

 chemical processes. 



Let us select an example. It is an hereditary charac- 

 ter of by far the greatest number of plants to produce 

 malic acid for the purpose of preserving their turgor, and 

 to store it in their cell-sap, most frequently in connection 

 with inorganic bases. We cannot imagine the secretion 



^Strasburger, E. Neue Untersuchungen iiber den Befruchtungs- 

 vorgang bei den Phanerogamen, p. 111. 1884. See also Weismann, 

 A., Die Kontimiitdt des Keimplasmas als Grundlage einer Theorie 

 der Vererbung, p. 28. 1885. Cf. Translator's Preface, p. viii. 



