210 Bulletin 236. 



Cultural characters. — Pure cultures obtained from the sources al- 

 ready detailed on pages 208-209 were grown in the different media during 

 July and August at ordinary room temperature. The media were all 

 titrated to 1.5 acid unless otherwise noted. The work was done in the 

 Bacteriological Laboratory of the State Veterinary College. 



Gelatine plates. — Growth very slow, colonies becoming evident in 

 about three to five days as tiny specks. Under the low power of the 

 microscope they appear as small globose or lenticular growths, sharply 

 outlined, yellowish. Surface colonies slowly liquifying the gelatin, form- 

 ing little pits. 



Agar plates. — Colonies evident by the second day, becoming char- 

 acteristic by the fourth or fifth day. The surface colonies are then from 

 two to three mm. in diameter in the form of a thin, white, finely granular 

 or cloudy circular growth with a dense, sharply defined white center ; 

 margins even or slightly wav3^ Deep colonies somewhat larger than the 

 central mass of the surface colonies, globose or more often lens-shaped, 

 dense opaque, yellowish. Under the microscope the central mass of the 

 surface colonies and the entire deep colonies appear opaque, homogeneous 

 and sharply defined, yellowish. The surface growth is coarsely granular 

 or flocculent, whitish. 



Potato bouillon. — Becomes uniformly and moderately clouded in 24 

 hours. When shaken shows waves or clouds from the surface into the 

 lower liquid, indicating that growth is most active at the surface; with 

 slight setliment and flocci, the flocci are: easily dissipated on shaking; 

 slightly acid to litmus paper. After about 48 hours the liquid becomes 

 uniformly and heavily clouded. Flocci more aboundant and more or less 

 persistent. Alkaline. After about 20 days the liquid becomes clear above 

 with abundant sediment and flocci at the bottom and strongly alkaline. 

 No odor ever developed. 



Beef bouillon. — Becomes faintly an! uniformly clouded after 24 

 hours vv'ith flocci and sediment, slightly acid. After 48 hours cloudiness 

 slightly increased. Flocci abundant and more or less persistent, neutral to 

 litmus paper, becoming finally strongly alkaline and after 20 days showing 

 tendency to clear. Odor not marked. 



Sugar free bouillon. — Perfectly clear after 24 hours, the only evi- 

 dence of growth being a slight sediment at the bottom. Neutral to litmus 

 paper. After several days becoming faintly cloudy and alkaline. No 

 indol produced. 



Agar slant. — Growth in 24 hours, moderate, glistening white opal- 

 escent, thick but not spreading much, often in isolated circular colonies 

 above, becoming more diffuse and spreading below toward the water at 

 the base of the slant. Water of condensation turpid and with flocci. 

 Growth not viscid. Increase of growth after this time very slight. 



