166 ROYAL SOCIETY OF CANADA 



on such media as beef peptone agar, peptone solutions, and beef 

 peptone bouillon; hence these experiments suggested that we could 

 use sBScuhn media for the isolation of B. tyyhosus from excreta and 

 other sources in the same manner as the Drigalski-Conradi medium. 

 We have tried the sesculin media for mixtures of B. coH and B. 

 typhosus, with good results. 



In addition to the results given in the table, cultures of all these 

 organisms have been made on sloped sesculin agar — only the colon 

 bacillus turned this medium black, all the others grew well but pro- 

 duced no discoloration. 



The synthetic media of Dolt combined with aescuhn, did not 

 give very satisfactory results. When the colon bacillus grew in these 

 media, black colonies with fields were formed, but they were as a 

 rule very small and not distinct. In a second series of experiments 

 we doubled the amount of chemicals in these media and added sesculin, 

 in our endeavour to obtain larger fields, but the results were no better 

 than before. For the growth of B. typhosus and B. dysenteriœ, Dolt's 

 media with sescuHn did not give good results; growth was hmited 

 in amount with the majority of species, and in some cases no 

 growth could be seen after 72 hours' incubation at 37°C. 



REFERENCES. 



(1) Harrison & Vanderleck. Centralblatt f. Bakt. II. Abte., 22 pp. 547 and 551, 



1909. 



(2) Saccardo. Chromotaxia seu nomenclator colorum. Patavii, 1894. 



(3) Beilstein. Organischechemie III. Auflage, pp. 566 and 608. 



(4) Dolt, M. L. Simple synthetic media for the growth of B. coll and for its 

 Isolation from water. — Journal of Infectious Diseases V., p. 616, 1908. 



(5) Conn & Esten. Report of the Storrs Agi. Expt. Sta., 1904, page 9. 



(6) Duval, C. W. Journal Amer. Med. Ass., 1904. 



Duval & Schoerer. Memoirs Rockefeller Institute Medical Research, 1904. 



