350 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. 



conditions have a wine-colored liquid. Litmus was slowly changed so 

 as to give a pinkish or wine-colored appearance to liquid, sometimes 

 after one to two months. 



Methylene Blue Milk. This medium was made by adding 2 per cent 

 aqueous solution of methylene blue (Merck) to milk and sterilizing 

 same. In one to two days at 19 to 20 C. the color completely dis- 

 appeared and could be restored by boiling or shaking the liquid in the 

 tube a few minutes. The disappearance of color seems to take place 

 first at the lower part of tube. The color entirely disappears some time 

 before separation of casein can be detected. 



Plant Juices. The walnut organism grows well in plant juices. 

 While no great number has been tested, the following extracts gave 

 abundant growth: Leaves of walnut (Juglans regia), loquat, castor 

 bean and fig. A ring formation and pellicle as well as a flocculent 

 precipitate are produced in these media. 



Viability in Media. In order to test the period of viability, transfers 

 were made to potato cylinders from milk culture at the end of five, 

 seven and eight months. Growth resulted in several cases. Old potato 

 cylinders were also tested. All these cultures were growing in dark 

 at a temperature from 15 to 20 C. 



From potato cultures made December 10, 1910, transfers were made 

 on September 28, 1911, a period of about nine and one half months. 

 On October 4, 1911, there was growth in one of the two tubes tested, 

 the other showing fungus growth. These old potato cultures just 

 referred to seemed to be thoroughly dried out, hard, and for the most 

 part brittle. When placed in the liquid of the potato cylinder tube 

 the old, dried-out portion absorbed water, becoming swollen and more 

 like its former viscid condition. Another potato culture six and one 

 half months old also produced fine growth when transferred to sterile 

 potato cylinders. In these cases of old potato cultures it is perhaps more 

 an instance of resistance to desiccation, also possibly this resistance may 

 be due to spore formation, although these have never thus far been 

 demonstrated. 



Indol. This reaction was tested in Dunham solution made as fol- 

 lows: Witte's peptone 1 per cent, sodium chloride 0.5 per cent, and 

 distilled water. After two weeks, the cultures were tested for indol 

 with sodium nitrate 0.02 per cent and a few drops of concentrated 

 sulphuric acid. The tubes after treatment did not at once show the 

 characteristic pink reaction, but when warmed for five minutes at 75 

 to 80 C. in a hot water bath, a strong indol reaction resulted, the color 

 being deep cherry red. 



Nitrate Reduction. A meat-peptone medium was used that titrated 

 plus 12 Fuller's scale. It was made after this formula: 1 per cent 



