26 Society for Experimental Biology and Medicine. 



kidney extract. In each case it was found that hemolysis was in- 

 hibited. The question therefore arises, why are kidneys suffused 

 with blood as a rule more actively hemolytic than the bloodless 

 organs ? If their extracts are centrifuged, and all the solid par- 

 ticles, including the red cells, removed, it is found that the extracts 

 are still deeply stained by hemoglobin. This is due to the de- 

 struction and solution of red cells, which is inseparable from the 

 process of preparing the extract. The next step, therefore, was 

 to determine the effect of adding red cell constituents to the blood- 

 less organ extracts. This was accomplished by adding red cells 

 to distilled water, and then bringing the solution to the strength of 

 normal salt solution. Such a solution adds very markedly to the 

 hemolytic power of the organ extract. Its manner of action seems 

 to resemble that of complement, inasmuch as it is capable of break- 

 ing up the red cells only after a preliminary treatment with the 

 organ extract. 



Tumors were investigated in the same manner as the kidneys. 

 It was found that the non-necrotic tumors are somewhat more 

 hemolytic than are the kidneys, owing possibly to their blood con- 

 tent. They act, however, in other ways precisely like the latter, 

 their action being diminished by the addition of serum and of white 

 cells, and of being increased by the red cell extract. 



Necrotic areas of tumors are extremely hemolytic, even up to 

 dilutions of two to four hundred. This hemolytic activity is not 

 affected by the addition of the blood components. 



An experimental study was made of the action of a necrotic 

 organ, by ligating the vessels and removing the organ after 

 several days. The extract was hemolytic in a dilution of one in 

 6,000. It acted in other respects like the extract of necrotic 

 tumors. 



24 (167) 



The enzymotic properties of diplococcus intracellularis. 

 By Simon flexner. 



[From the Rockefeller Institute for Medical Research.'} 



The brief vitality of many of the cultures of diplococcus intra- 

 cellularis is a point of differential importance. Many strains, 

 grown on a favorable medium, unless transplanted to a fresh 



