10 



L. A. JULIANELLE 



that the 6 days were not sufficient. Other cultures not included in this 

 survey did show hemolysis after the arbitrarily chosen time, and 

 attempts to collect nonhemolytic strains after 10 and in rarer cases 12 

 days, have failed. So that it seems by virtue of this evidence that 

 the strains we originally labeled nonhemolytic were in reality hemolytic, 

 and that their hemolytic character was very much suppressed. It 

 would seem, therefore, that it can be definitely stated that cultures 

 which did not show hemolysis within 6 days were able to give definite 

 signs of hemolysis on blood plates within 24 hours and complete 

 hemolysis within 48 hours. 



Since the completion of this experiment every strain of staphylo- 

 coccus isolated (whether a contaminant or a pathogen) was held for 

 study. The number of days required to show beginning hemolysis was 

 recorded. These results are tabulated in table 4. It will be seen that 

 every strain shows hemolysis, but that the factor of time plays an 



TABLE 3 

 DEVELOPMENT OF HEMOLYSIS BY NONHEMOLYTIC ? STRAINS 



important part. Thus it is seen that in a general way aureus strains 

 show hemolysis earlier, and that virulent strains also show hemolysis 

 earlier than the saprophytic ; but the point is clear that white and aureus 

 strains, saprophytic and parasitic alike, become hemolytic. In the case of 

 nipples, for example : These are supposedly sterilized and sent to the 

 laboratory to be tested for sterility so that it is logical to assume that any 

 growth is apt to be contamination. Yet the 9 white strains are as 

 rapidly hemolytic as the 18 orange strains isolated from pus. 



Effect of Carbohydrates on Hemolysis. It has been shown by 

 Ruediger, 10 Lyall, 11 Davis, 12 Sekiguchi, 13 Stevens and Koser 14 and 



"> Ibid., 1906, 3, p. 663. 



Jour. Med. Res., 1914, 30, p. SIS. 



Davis: Jour. Infect. Dis., 1917, 21, p. 308. 



" Ibid., 1917, 21, p. 475. 



14 Jour. Exper. Med., 1919, 30, p. 539. 



