TRANSACTIONS OF SECTION I. 545 



glass, or wood or cotton fibres, all of which are of a non-greasy nature. Such 

 cells have been shown to be highly phagocytic for particles of Indian ink or 

 carmine. Indeed, among the various forms of invertebrate cells those which 

 possess in highest degree this phagocytic power for Indian ink particles are 

 precisely those which flatten out most promptly on glass. The phagocytosis of such 

 particles is a purely physical phenomenon conditioned by the greater attraction 

 of cell molecules over plasma molecules for the particle in question. A minute 

 fragment of Indian ink, having accidentally come in contact with the cell, the 

 cytoplasm simply creeps over it, displacing the plasma until the fragment is 

 engulfed. Cells such as these, which phagocyte Indian ink particles have no 

 power to phagocyte fat particles present in a fine emulsion. 



The process of diapedesis of leucocytes may possibly be explained on similar 

 principles. Arnold showed that diapedesis occurs at certain spots situated at 

 the junction of the endothelial cells, where presumably some of the extra-endo- 

 thelial tissue is temporarily exposed. To this the cell adheres. Because of the 

 molecular attraction between cell substance and the fluid or semi-fluid extra- 

 endothelial material, the surface tension of the cell is locally reduced over the 

 adhering area, whereas it remains relatively high over the portion still covered 

 by plasma. The consequence is that the cell is forced continuously outwards. 



3. Nutritive Values of Wholemeal and White Flour. By Miss May Yates. 



TUESDAY, SEPTEMBER 5. 



The following Papers were read :— 



1. On the Influence of Iodoform, Chloroform, and other Substances, dissoluble 

 in Fats, on Phagocytosis. By H. J. Hamburger, Sc.D., M.D., LL.D. 



In the last four years I have occupied myself with Messrs. E. Hekma, J. de 

 Haan, and F. Bubanovic on the physiology of phagocytes. 1 The present paper 

 forms a continuation of these investigations, but has a pharmacological point of 

 issue. For the last thirty years iodoform has been successfully applied in the 

 treatment of wounds and chronic inflammations. Several hypotheses have been 

 suggested to explain its favourable action, but none of them have proved to be 

 generally satisfactory. 



Having observed in what small quantities calcium could accelerate phago- 

 cytosis, the idea came to me that iodoform might have the same effect. 



The method of investigation adopted corresponded entirely to that we fol- 

 lowed in former researches. We settled the percentage of leucocytes, having 

 taken up carbon in case of addition of iodoform, and without this, to the 09 

 per cent. NaCl-solution. 



The results were not doubtful; iodoform promoted phagocytosis to a con- 

 siderable extent. The effect was still plainly visible in a fluid containing 1 gr. 

 CHI, to 5,000,000 c.c. NaCl-solution 09 per cent., or 1 gr. mol. CHI 3 to 

 1,900,000 L. of the NaCl-solution. 



What could be the reason of this acceleration ? We may take it for granted 

 from numerous investigations that the outer layer of cells consists in a fat sub- 

 stance, a so-called lipoid membrane. Further, it is a well-known fact that 

 iodoform is soluble in fat. Now it is obvious that by taking up iodoform the 

 lipoid membrane will grow more flexible; in other words, the surface tension 

 will decrease and consequently the amoeboid motion will be facilitated. Hence 

 an acceleration of phagocytosis. If this interpretation was the correct one, then 

 it might be expected that other substances which are soluble in fat would affect 



1 Cf. Biochemische Zeitschr. and Proceedings of Royal Society Amsterdam. 

 1911. N N 



