CULTURAL CHAEACTEES OF THE DAISY ORGANISM. Ill 



Stahs. — In gelatin stahs the growth is best at the top; the line of punc- 

 ture is filiform; liquefaction is absent, and the medium is not stained. 

 It did not make an abundant growth. 



loeffler's blood serum. 



Medium not liquefied. After 14 days at about 26° C. the growth 

 along the streak was moderate, filiform, flat, glistening, and smooth; 

 color white, tending toward cream in the old cultures. The medium 

 was slightly grayed below the condensation water. 



NUTRIENT BEEF BROTH." 



Clouding often absent or inconspicuous; a rijn of gelatinous threads 

 and more or less pellicle; also in young cultures very delicate suspended 

 short filaments, best seen on shaking. In 48 hours after inoculating 

 from bouillon there was no surface growth and no clouding; there was 

 a slight, usually filamentous sediment, which became visible upon 

 shaking the tube containing the culture. On thorough shaking the 

 fluid becomes thinly clouded with numerous white suspended delicate 

 threads (1 to 10 mm. or more in length). Under the microscope 

 these threads are seen to be made of innumerable closely compacted 

 small rods several times as long as broad. In 4 days a ring had 

 formed, but the clouding of the liquid was either absent or not notice- 

 able, although long gelatinous threads extended from the ring at the 

 top to the bottom of the broth. These threads appeared to flatten out 

 at the lower ends, forming a flocculent sediment. In cultures 3 weeks 

 old the same phenomena were conspicuous. When stained with carbol 

 fuchsin, there were many much swollen, irregularly staining, vacuo- 

 late, branched slime threads containing bacteria (fig. 3). In old cul- 

 tures (7 weeks) the strings when examined under the microscope 

 appeared in the form of irregular fine threads more or less vacuolate. 

 At first these threads were taken for bacterial filaments undergoing 

 disorganization, but on further study and careful staining they proved 

 to be slime threads containing numerous involution forms and unmodi- 

 fied bacteria. No odor is noticeable in these cultures. There is often 

 no true pellicle, only what might be termed an interrupted one. At 

 other times, especially on standing for some weeks undisturbed, a true 

 pellicle forms which fragments on shaking. It may be mentioned, 

 however, that in a strain under cultivation for three years a continu- 

 ous thick firm (nonfragmenting) pellicle finally formed, and coinci- 

 dent with this the virulence greatly lessened. 



Sometimes in 12 hours at 25° C, when inoculated copiously from a 

 young culture, the bouillon contains numerous suspended delicate 

 filaments easily visible, especially on shaking. 



o Containing 1 percent Witte's peptone and sodium hydrate to read +15 on Fuller's scale. 

 213 



