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J. M. SHERMAN AND W. R. ALBUS 



inoculated with milk is evidence of fecal contamination, while 

 Rogers, Clark and Evans (1916) believe from their results that 

 it is indicative of infected udders in some of the milk producing 

 animals. In our tests the streptococci from the udder- grew 

 more feebly in bile than did the lactic-acid streptococci, and, 

 in most cases, could be found only with difficulty in microscopic 

 preparations. When examined after two days incubation at 

 37°C. bacteria were observed in only 17 of the 50 cultures. 

 Those seen were all in typical chain formation. 



In table 1 is presented a summary of the results obtained in 

 this study. The examinations of broth and agar cultures were 

 made after incubation at 37°C. for one day. The growth ex- 



TABLE 1 

 Chain formation on agar, broth and bile 



Chains on lactose agar 



Chains on glucose broth 



Chains on lactose-peptone-bile. 

 Chains predominating on broth 

 Chains predominating on bile . 



amined from agar was taken from the sloped surface, not from 

 the water of condensation. Chain formation was not recorded 

 as positive unless definite chains of ten or more cells in length 

 were seen. 



These data indicate that some distinction may be drawn 

 between these two groups of streptococci based upon cell group- 

 ing. For example, all of the cultures numbered from 51 to 100 

 showed chains on agar and broth, while this was true of only 

 about one-half of the organisms from the other group. If con- 

 sideration is taken of the grouping of the majority of cells a 

 greater difference is seen. On broth in all of the streptococci 

 of the udder type the predominating arrangement was in chains 

 whereas this was the case in only about one-fourth of the other 

 cultures. 



