OF VITAL PHENOMENA 179 



corpuscle. C0 2 is bubbled through, the titratable alkalinity of 

 the pure Na 2 CO s solution is found to be increased because Na- 

 Protein is changed to H-Protein + NaHC0 3 and the latter dif- 

 fuses into the pure solution. As is readily seen, the analogy is 

 not exact. 



It is possible that the plasma membrane of the erythrocyte is 

 different from that of other cells. The stroma of these cells 

 contain a large percentage of lecithin and cholesterin. Pascucci 

 (1907) made membranes of lecithin and cholesterin that could 

 be laked with the same reagents that lake corpuscles. These 

 membranes were more easily laked the greater the percentage of 

 lecithin, the same being true of corpuscles. Perhaps some laking 

 agents combine with lecithin. Berczeller (1914) found that the 

 surface tension of alkaline solutions of lecithin is increased by 

 the addition of chloroform or ether. The relation of lecithin 

 and cholesterin in the serum to certain hemolysins has been much 

 studied, lecithin favoring and cholesterin inhibiting hemolysis. 

 According to von Dungern and Coca (1908 a, b, c) the hemoly- 

 sin in snake venom is a lipase that splits off fatty acid from the 

 lecithin, and the latter hemolyzes the corpuscles. Iscovesco 

 (1910 c) claims that cholesterin inhibits the action of lecithin by 

 combining with it. Lecithin reduces the surface tension of water, 

 but on addition of cholesterin it rises again. He claims that 

 cholesterin acts on soap in the same manner. 



Though anesthetics in high concentration are hemolytic, 

 Traube (1908 a) found that small doses inhibit hemolysis. He 

 claims that hemoglobin, itself, when in the serum, is hemolytic, 

 but his specimen of hemoglobin was apparently impure. 



The relative volume of corpuscles and plasma may be deter- 

 mined with the hematocrit (Hedin) or calculated from the con- 

 ductivity (Stewart) volume of corpuscles 

 conductivity of blood 



= 92 — — : 1" x 3- 



conductivity of serum 



The hematocrit was used by Hamburger to find the osmotic 

 pressure on the assumption that the corpuscles are impermeable, 

 although, in a series of later papers, he claims that they are freely 

 permeable. 



The viscosity of the blood is determined by the total volume 



