METHODS OF PURE CULTURE STUDY 



PRELIMINARY REPORT OF THE COMMITTEE ON THE CHART 

 FOR IDENTIFICATION OF BACTERIAL SPECIESi 



H. J. CONN, Chairman, H. A. HARDING, I. J. KLIGLER, W. D. FROST, 

 M. J. PRUCHA, AND K. N. ATKINS 



The following methods have been prepared primarily to 

 accompany the chart recommended at the 1917 meeting for use 

 in instruction in bacteriology. So far as they apply, they should 

 also be used for the older chart; but many of the determinations 

 called for by the older chart have not yet been studied by the 

 committee, and are not included in this report. It is the desire 

 of the committee that these methods be put in provisional use 

 during 1918, and that they be adopted as standard methods at 

 the 1918 meeting, after such changes have been made in them as 

 the year's use shows to be necessary. The chairman of the 

 committee will be glad to receive suggestions in regard to such 

 changes. Reprints of this report may be obtained from the 

 secretary of the society at about cost price. 



PREPARATION OF MEDIA 



Beef-extract broth shall have the following composition: 



Beef-extract 3 grams 



Peptone , 5 grams 



Distilled water 1000 cc. 



Beef-extract agar shall be of the same composition plus the 

 addition of 12 grams of oven-dried agar or 15 grams of com- 

 mercial agar. Beef-extract gelatin shall be of the same com- 

 position, with the addition of 120 grams of Gold Label gelatin, 

 or 100 grams of some brand of gelatin (such as '^Bacto-gelatin," 

 or United States Glue Company gelatin) having greater jellying 



^ Presented at the Washington meeting of the Society of American Bacteri- 

 ologists, December 28, 1917. 



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