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Scientific Proceedings (128) 



cercariae obtained from specimens of Blanfordia nosophora from 

 Japan. In both cases serial microscopic sections of snails so ex- 

 posed showed the successful penetration of the snail by the 

 miracidia. The biological similarity of the Japanese and Chinese 

 forms of Schistosoma japonicum is therefore demonstrated. 



106 (2066) 



Factors controlling the electrolyte and water distribution 

 in the blood. 



By D. D. VAN SLYKE, HSIEN WU, and FRANKLIN C. McLEAN. 



[From the Laboratory of Physiological Chemistry and the Chemical 

 Laboratory of the Department of Medicine, Peking Union 

 Medical College, Peking, China.] 



In combining the known facts to form an inclusive quantita- 

 tive expression of the phenomena of electrolyte and water dis- 

 tribution we have assumed for the blood the validity of the fol- 

 lowing physico-chemical laws : 



I. At and near the neutral point all strong alkalies are in the 

 form of salts. At blood reaction therefore the total base may 

 be represented as BP + BA, when BP represents the alkali pro- 

 tein salts, BA the salts bound by the alkali with other negative 

 radicles, chiefly CI' and HC0 3 '. 



II. The law of Donnan governing the influence of non-per- 

 meating ions on the distribution of permeating ions on the two 

 sides of a membrane holds for the membranes of the blood cells. 

 Donnan's theory has been provided with a sound basis of experi- 

 mental proof by Donnan, by Proctor and Wilson, and especially 

 by Loeb's recent study on the osomotic and electrical behaviors 

 of protein solutions. 



III. The osmotic activity of each solute is proportional to 

 the ratio n : N, of gram molecules of solute to gram molecules of 

 water. The presence of the serum proteins, according to the 

 vapor tension determinations of Neuhausen, does not affect the 



