18 A SOFT ROT OF THE CALL A LILY. 



face of the agar. The outlines were .sharp and when magnified 125 

 times the 4S-hour-old colonies had a granular appearance. 



Af/ar strrcd- cultures. — In addition to beef broth, peptone, etc., some 

 of the agar tubes contained 5 per cent of grape sugar and others con- 

 tained 5 per cent of gh'cerin. These were slanted and inoculated by 

 dipping a sterilized needle in a Q-t-hour-old beef-broth culture and 

 drawing it lightly over the surface of the slant agar. Streaks became 

 distinctl}" visible in twent}-four hours at 20- to 25^ C. in all the 

 tubes inoculated. The outlines of the streaks were entire at first, 

 but became more or less irregular in from two to four davs at IS*-* to 

 25^ C. Growth was elevated above the surface of the agar and had a 

 shiny appearance, as if wet. It was of a white or grayish-white color 

 and did not discolor the agar nor tend to grow into it. The condensa- 

 tion water became distinctly milky and more or less deposit was 

 formed in it. On the other agars the organism remained alive for 

 several months at room temperatures (20° to 25° C.) if the culture was 

 not allowed to become dr}'. 



Agar staJj cultures. — At room temperatures (20° to 25° C.) growth 

 was apparent in from eighteen to twenty-four hours near the top of 

 the stab, and within twenty-eight hours it was distinctly visible 

 throughout the entire length of the stab. The stab increased in size 

 from day to day and in a week was from 1 to 2 mm. in diameter, 

 slightlv tapering toward the bottom. The '"nail head" gradually 

 increased in size and in from three to five days covered the surface of 

 the agar iu the tube. This growth was slightly elevated, grayish- 

 white, with a wet. shining surface and an entire margin. It was 

 thicker in the center, forming a convex layer on the agar. Growth 

 continued for several weeks, with no change in the color of the agar 

 and no change in the stab or line of growth except that it gradualh" 

 increased in size, retaining its tapering form and its slightly serrate 

 outline with no elongated projections into the agar. 



Bt-ef agar., vyith Iron suJpJiate. — Several slant tubes containing 10 c. c. 

 of nutrient agar plus 1 drop of a .saturated solution of ferrous sulphate, 

 and several slant tubes containing 10 c. c. of nutrient agar plus 2 drops 

 of the iron sulphate solution, were inoculated with a fresh culture of 

 the calla organism, while several tubes of each were left for control. 

 In fort^'-eight hours the organism had spread over the surface of the 

 agar in all inoculated tubes and the inorulated surfaces showed a copi- 

 ous growth for several weeks, but no change was produced in the 

 color of the medium. 



Gelatin stah cultures. — The.se cultures were made with gelatin of dif- 

 ferent kinds. The first was —10 on Fuller's scale, the second was neu- 

 tralized with .sodium hydroxid, while the third was the same as the 

 .second except that another kind of gelatin was used. Growth was 

 apparent within twenty-four hours (at 18° to 22° C.) in all the tubes 



