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potato received the most bacteria. The tests were made from solid 

 and fluid cultures and into two kinds of beef bouillon, viz: (1) Stock 

 577, a standard salted peptonized beef broth +15 of Fuller's scale, 

 which had dried out one-fourth b}^ long standing; (2) stock 579, a 

 flask of stock 577 diluted with an equal bulk of distilled water before 

 it was filled into the test tubes. When everj^thing was readj^ for the 

 test, the dishes were brought out of the closet, and in clean, still air 

 the inoculated covers were seized with sterile forceps and dropped one 

 after another into the tubes of beef liouillon, which were then replugged, 

 set away in the dark, and watched for six weeks. 

 These experiments were as follows: 



(1) Ps. camjK'Stris. — Covers inoculated copiousl}' from the yellow 

 slime on a potato culture 2 days old. Dry 31 days. 



a. Covers thrown into stock 577 — 12 tubes. 



Result: One tube clouded on the 3d day and one on the 1th day. 

 The other 10 remained clear. The clouding was typical for this 

 orp-anism, and cultures made from each of the tubes into potato yielded 

 a tj^pical growth of Ps. camjjestris. 



h. Covers thrown into stock 579 — 12 tubes. 



Result: Six tubes were cloudy on the 3d day, 6 remained clear. 

 The clouding was typical, and cultures from each of the 6 tubes into 

 tubes of potato yielded in each case pure cultures of Ps. camjyestris. 



(2) Piu camj>estris.—^^Q\i cover inoculated with a small drop of 

 moderatelv cloudv fluid from a beef broth culture 2 days old. Dry 34 

 days. 



a. Covers thrown into stock 577 — 11 tubes. 



Result: No growth in any of the tubes. 



I. Covers thrown into stock 579 — 12 tubes. 



Result: Two tubes clouded on the 3d day. The rest remained clear. 

 The clouding was typical, and transfers from the tubes into tubes of 

 potato yielded pure cultures of Ps. campestris. 



(3) Ps. 2)haseoli.— Coy evs inoculated copiously with the yellow slime 

 from a potato culture 3 days old. Dry 27 days. 



a. Covers thrown into stock 577 — 9 tubes. 



Result: One tube clouded on the 3d day, one on the 5fh day, and 

 one on the 6th day. The rest remained free. The clouding was typical, 

 and cultures from each tube into potato yielded a pure growth of 

 Ps. 2>JHiseolL : 



I. Covers thrown into stock 579—12 tubes. 



Result: Two tubes clouded on the 3d day and 2 on the 4th day. The 

 rest remained free. The clouding was typical, and cultures from each 

 of the tubes into tubes of potato yielded a typical growth of Ps. 

 jphaseoli. 



(4) Ps. i>liaseoJi.—Y.'AQ\y cover inoculated with a small drop from a 

 well-clouded beef-)n-oth culture 3 days old. Dry 27 days. 



