280 Cc. U. ARIENS KAPPERS 
Now we know from the chemical examinations of Grandry* 
and Macallum and Menten* that KCl is hardly present in the 
cell and the dendrite, so that for us there is no reason here to 
expect an anodal kataphoresis. 
Looked at from the point of view of Hardy’s investigations, 
which according to Greeley* we may apply to intra-protoplas- 
matic colloidal granules, there are perhaps more arguments 
which favor the shifting of the dendrites, and later of the cell- 
body, in the direction of the stimulus. For we know that the 
dendrites and the cell-body differ from the axis-cylinder by 
the presence of Nissl’s substance which during life is probably 
in a more or less fluid condition (see Cowdry’s papers** on the 
bio-chemical conditions of nerve cells). This substance is prob- 
ably a derivative or compound of nucleic acid*’ and the presence 
of acid in it will, according to Hardy’s investigations, promote 
the shifting of the colloids which are suspended in them to the 
kathode. While, therefore, the absence of a larger quantity of 
KCl does not prevent the first outgrowth of the dendrite from 
proceeding in the kathodiec direction, the presence of acid nuclein 
derivatives would even promote it. 
°8 Grandry. Recherches sur le structure du cylindre-axe et des cellules 
nerveuses. Bulletin de l’ Academie de Bruxelles, 2 me Series, vol. 28, 1868, p. 304. 
Idem. Journal de l’Anatomie et de la Physiologie, vol. 6, 1869, p. 289. 
*4 Macallum and Menten. Distribution of chlorides in nerve-cells and fibers, 
Proceedings of the Royal Society, vol. 76B, 1905, p. 217. 
Macallum. Die Ergebnisse und Methoden der Microchemie in der biologis- 
chen Forschung. Ergebnisse der Physiologie von Asher und Spiro, Jahrg. 7, 
1908, p. 697. 
* Greeley. Experiments on the physical structure of protoplasm of Para- 
mecium and its relation to the reactions of the organism to thermal, chemical, 
and electrical stimuli. Biological Bulletin, vol. 7, 1904. 
8° Cowdry. The development of the cytoplasmatic constituents of the nerve- 
cells in the chick. Mitochondria and neurofibrils. Am. Jour. Anat., vol. 15, 
1912. 
Cowdry. The relations of mitochondria and other protoplasmatic constitu- 
ents in spinal ganglion cells of the pigeon. Internationale Monatschrift fiir 
Anatomie und Physiologie, Bd. 29, 1913. 
Cowdry. The general function and significance of mitochondria. Am. 
Jour. Anat., vol. 19, 1916. 
‘7M. A. Van Herwerden. Ueber die Nuclear-wirkung auf tiersche Zellen. 
Kin Beitrag zur Chromidienfrage. Archiv f. Zellforschung, Bd. 10, 1913. 
