Cell Formation and Division J. TRAUBE Edinburg?1, Scotland
T.
HE processes of cell formation and division, so diffusion and a formation of spindles and astrospheres Important as biological phenomena, have been corresponding to the formation of spindles in biofrequently simulated, if not reproduced, in a logical cells. This radiation proceeded from central number of non-biological systems. T h e formation poles which can, for example, result from air bubbles. and division of "cells" in such c a x s is obviouslv ,broueht Fields of force, similar to those assumed by Faraday, about by surface and interfacial forces. These same were produced. Every point a t which the concentraforces are doubtless effective in all actions occurring tion is greater than that of the surrounding medium in the protoplasm. One stage in the mechanism of cell can be considered as a center of attracting or repelling formation and division is the establishment of "poles" in the protoplasm, which act as central points from which diffusion takes place. These poles may even be formed by gas bubbles. Among those who have experimented on non-biological systems may be mentioned Leduc, Rhnmbler. Bluntschli, Spek, and others.' The work of Leduc is perhaps worth special attention. He observed remarkable cell-like formations when water containing China ink was dropped into aqueous solutions of sodium chloride or potassium nitrate. Diffusion effects result in the formation of a number of adjacent "cells" simultaneously, while in the biological phenomenon
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cell formation, as a result of division, is of course a consecutive process. Leduc observed a radiation by A B D E ~ L D EEditor, N, "Handbuch der biologischen Arbeitsmethoden, Urban and Schwarzenberg, Berlin, 1921-23, Abt. 5, Teil 3.4.
force, giving rise to diffusion currents in one direction or the other. Some years ago the author was trying to develop the technic of Droducing certain bright-colored formations on glass&re.2 Fkster of is was moistened with varying amounts of d i e r e n t salt solutions, applied in spots to the inside of the glassware, and dried. Figure 1shows a vase made in this way, with a number of nuclei of the plaster on the inner surface, moistened
TRA~E "Kolloide , Vorginge heim Binden des Gipses. Strukturen in Gim." Kolloid-Z.. 25, 62-6 (1919).
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with femc chloride solution. After the plaster had near the nuclei. A thick wall forms between adjacent partially set, a paste made up with more plaster of nuclei, which eventually unites with the cell walls. Paris moistened with potassium ferrocyanide solution I n this connection, notice particularly the small cells was poured over the inside of the vase and allowed a t the top of the vase, as well as the constriction in the to set over the previous plaster masses. The blue cells in which the division appears to be going on. color of ferric ferrocyanide which resulted was separated bv white cell walls of a ~recioitatedwhite substance containing gypsum (the more highly hydrated calcium sulfate). The appearance is very much like that of the cell structures in protoplasm resulting from the colloids there. The plaster nuclei correspond to the nuclei in the protoplasm and in each case there is only one nucleus in each cell. There seems to be a close analogy between these two kinds of cell formation, and especially as regards the forces of diffusion which operate. From the plaster nuclei there is a diffusion of salt to the covering layer of plaster containing ferncyanide, as well as a diffusion in the opposite direction. As in the case of cataphoretic migration there is a neutral point a t which precipitation and deposition take place. It is here that cell walls are formed as a result of diffusion effects. These experiments seem to supplement those of Leduc. The formations in the second vase (Figures 2 and 3) are especially characteristic. This was made in the same way as the first, just described. One will immediately observe the small cells in the upper part, which are formed from gas bubbles. Each nucleus corresponds to one cell of which it is the parent. Especially noticeable is the beginning of the process of cell division which can be seen in its various stages in adjacent cells. The Liesegang structure is observable in the larger cells, forming a number of parallel cell walls. This effect can only be the result of "rays" from the central body. I n biological cell formation this effect consists in the formation of spindles, a process which has its counterpart here in the bluish white radiation surrounding the plaster masses, and in which the indiThese results seem to the author more striking than vidual &ys can be easily distinguished by different those of Leduc in simulating the consecutive formation shades of color. It is remarkable that the division of cells begins of cells.
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