62 Titaliiy and Organization of Protoplasm. 



also fragments of germs^ are endowed ^Yith an intrinsic formative power 

 capable of reconstituting specific tissues and forms, which are organized 

 down to their minutest component parts, and throughout alive to their 

 innermost core. This formative and vitalizing feat on the part of small 

 fragments of germ-plasm surpasses incommensurably anything that 

 mere mechanical actuation can possibly accomplish, and mere mechani- 

 cal arrangement can bring about. 



It has been shown that only by recognizing reproductive plasm to be 

 in every instance a specific cJiemical fragment of a specific chemical 

 whole, can we gain a scientific insight into this most wonderful of all 

 occurrences in perceptible nature; the faithful reproduction of a defi- 

 nitely predetermined and intricately constructed organism from a min- 

 ute bit of morphologically all but homegenous plasm. 



By means of ontogenetic experiments of the same kind, it was also 

 found that the nucleus, to which the entire formative potency had been 

 ascribed, does not really play any leading part in this formative process. 

 This conclusion is likewise of great importance to a right understanding 

 of ontogenetic processes. It may have been considered strange, that in 

 the section on "Vitality" no notice was taken of the nucleus, which is 

 still considered by many observers to be of paramount importance in the 

 actuation of vital phenomena. The discussion of the part it is taking 

 in vital processes has, however, been intentionally reserved for this and 

 other pertinent occasions. The study of the self-division of certain 

 Protozoa forced upon the present writer^ likewise the conclusion that 

 the nucleus is playing only a subordinate part in vital and formative 

 processes. In reference to the distinctly visible, clearly outlined nucleus 

 of gigantic amoeba, I remarked in the Jenasche Vieteljahrschrift fur 

 Naturwissenschaft, 1882, p. 689 : "As a self-rounded, sharj^ly outlined 

 granular body the nucleus of the amoeeba is pushed and rolled from 

 place to place during the creature's changing movements, and is forced 

 now in front, now behind, and again into any other position." "No 

 forrnative organic process determines for it from moment to moment 

 its specific position and form. It is not an integrant constituent of the 

 continuous cycle of activities to which the life of protoplasm owes its 

 existence. It is a persistently established accessory organ, whose gen- 

 eral function is not yet ascertained, but which presumably consists in 

 the absorption of oxygen." 



Sundry experiments performed since the above was written seem to 

 confirm the conjecture that the function of the nucleus is intimately 

 connected with the indispensable process of oxydation. To this con- 

 clusion Loeb has arrived, as explained in the Archiv fur Entzwicklungs- 

 Mechanic. 1899, p. 689. Pieces of non-nucleated living substance 

 quickly disintegrate, while pieces containing oxygen-absorbing chloro- 

 phyll retain their vitality for a long time. The fact that blood-cor- 

 puscles are absorbers of oxygen seemed to me also to favor the con- 

 jecture I had formed. For blood-corpuscles originate from nuclei de- 

 tached from the epithelium of lymphatic glands and form kindred kinds 



