STREPT. ERYSIPELATIS AND STREPT. LACTICUS. 181 



tions. Streptococcus erysipelatis has existed in the medium of an animal 

 body of which the reaction of blood is approximately Ph = 7.56 or (H) = 

 2.75X10"*;^ on the other hand, Streptococcus lacticus existed previous to 

 the isolation in the starter of which the reaction is about Ph = 5 or 

 (h) = 1X10"^'2 Considering these facts with the results obtained, the 

 correlation between the degree of growth in the medium of different 

 hydrogen ion concentration and their previous surroundings is indicated. 



Rate of Proteolysis.' 

 Table 3. — Proteolysis. 



Set 1 — Slreptococcus erysipelatis. 

 Set 2 — StreptococcTxs lacticus. 



Table 3 indicates the following: — 



Set 1 {Streptococcus erysipelatis). — The greatest proteolysis occurred 

 in flask 7, and practically no proteolysis in flask 5; at the end of six hours 

 proteolysis appeared. 



Set 2 {Streptococcus lacticus). — The greatest proteolytic activity was 

 manifested in flask 6 and practically none in flask 9; it was not until the 

 end of eighteen hours that slight proteolysis began to appear. 



' Michaelis, L. Die Wasserstoffionenkonzentration, Berlin, 101, 1914. 

 ' (jj) of starter from which the organism was isolated. 

 ' The method for determination has been described previously. 

 * Milligrams per 100 cubic centimeters. 



