NOT DESCRIBED IN PREVIOUS SECTIONS. 509 



rubbing, to the uninjured skin, but succumbed to subcutaneous injections in 

 twenty-four hours or between the fifth and tenth days. Those which died 

 at a late date presented the pathological appearances which characterize 

 pysemia. 



142. BACILLUS NO. I OF ROTH. 



Obtained by Roth (1890) from old rags. Resembles Bacillus coli com- 

 munis and Brieger's bacillus in its morphology and growth in various culture 

 media, but, according to Roth, is distinguished from these bacilli by the fact 

 that colonies upon gelatin plates are thicker and more opaque. 



Pathogenesis. Pathogenic for rabbits and for guinea-pigs when injected 

 into the cavity of the abdomen; death usually occurs within twenty-four 

 hours. The spleen is greatly enlarged, and the bacilli are found in cultures 

 from the blood and various organs. 



143. BACILLUS NO. II OF ROTH. 



Obtained by Roth (1890) from old rags. 



Morphology. Bacilli with round ends, 0.6 to 1 jo, broad and two to four 

 times as long. 



Stains with the usual aniline colors. When stained by Gram's method 

 it is decolorized by alcohol. 



Biological Characters. An aerobic and facultative anaerobic, non- 

 liquefying, non-motile bacillus. Grows in the usual culture media at the 

 room temperature. Upon gelatin plates colonies resembling those of the 

 <;olon bacillus are developed at the end of twenty-four hours ; on the third 

 day small, drop-like, shining, bluish-white colonies, around the periphery of 

 which a commencing extension upon the surface of the gelatin is seen. Older 

 colonies are seldom more than one-half centimetre in diameter, and are some- 

 what thicker than this ; they are nearly transparent. Upon the surface of 

 gelatin stick cultures a rather moist, yellowish-white layer with dentate 

 margins is developed. Upon potato a colorless layer is developed, which 

 later has a grayish color. 



Pathogenic for rabbits and guinea-pigs when injected into the abdominal 

 cavity. 



144. BACILLUS OF OKADA. 



Obtained by Okada (1891) from dust between the boards of a floor. 



Morphology. Short rods with round ends, about as long as Bacillus 

 murisepticus, but somewhat thicker about twice as long as thick ; solitary 

 or in pairs; in old cultures may grow out into filaments. 



Stains with the usual aniline colors, but not by Gram's method. 



Biological Characters. An aerobic and facultative anaerobic, non- 

 liquefying, non-motile bacillus. Does not form spores. Grows in the usual 

 culture media at the room temperature. Upon gelatin plates, at the end of 

 two to three days, small, white, spherical colonies are developed. Under 

 the microscope these are seen to be granular, pale-brown in color, and with 

 slightly jagged margins ; the superficial colonies after several days are con- 

 siderably elevated above the level of the gelatin. In gelatin stick cultures 

 development occurs as a white thread along the line of puncture, and upon 

 the surface as a flat, milk-white layer which does not extend to the walls of 

 the test tube. Upon agar, at 37 C., the growth is rapid and the surface is 

 nearly covered at the end of eighteen hours with a milk-white layer ; the con- 

 densation water is filled with a viscid mass of bacilli. Upon blood serum 

 the growth is shining and almost transparent. In bouillon development is 

 rapid, clouding the fluid throughout, and a cream-like layer forms upon the 

 surface. 



Pathogenesis. Rabbits and guinea-pigs die in about twenty hours after 

 receiving a subcutaneous injection of a half-syringeful of a bouillon cul- 

 ture, or from a small quantity (two ose) from a gelatin or agar culture. In 



