T DESCRIBED IN PREVIOUS SECTIONS. 497 



fluent and form, shining, wavy stripes. Upon potato the development is 

 more rapid and forms elevated, sharply denned colonies, of granular ap- 

 pearance and of a chamois-yellowish-white color ; later these become conflu- 

 ent; the potato acquires a dark-gray color and the culture gives off an in- 

 tensely disagreeable odor. 



Pathogenesis. Pure cultures rubbed into the skin of man produce, at 

 the end of twenty-four hours, intense itching, redness, and a vesicular erup- 

 tion about the hairs ; at the end of three days small pustules are formed, 

 from which pure cultures may be recovered (Tommasoli) . Subcutaneous in- 

 jection into a rabbit produced no other result than the formation of a small 

 abscess. 



114. BACILLUS OF SCHOU. 



Obtained by Schou (1885) in rabbits suffering from vagus pneumonia 

 resulting from section of the vagi ; found also in the buccal secretions of a 

 healthy rabbit one out of twenty-five examined. 



Morphology. Described as elliptical cocci, or diplococci, or as short, 

 thick bacilli. 



Stains with the aniline colors usually employed, but not by Gram's 

 method. 



Biological Characters. An aerobic, liquefying, motile bacillus. Grows 

 in the usual culture media at the room temperature. In gelatin plates 

 forms spherical, opaque, granular colonies having a slightly rough surface. 

 At the end of twenty -four hours, under the microscope, active movements 

 are observed in these colonies, which are surrounded by a zone of diverging 

 rays. In gelatin stick cultures liquefaction quickly occurs, and a copious 

 white deposit, consisting of bacilli, is seen at the bottom of the tube. 



Pathogenesis. Pure cultures injected into the trachea, the pleural 

 cavity, or the lungs are said to have produced fatal pneumonia in rabbits; a 

 similar result was obtained from inhalation experiments. 



115. BACILLUS NECROPHORUS. 



Obtained by Lofner (1884) from rabbits which had been inoculated in the 

 anterior chamber of the eye with small fragments of a broad condyloma. 



Morphology. Bacilli of various lengths, often forming long, slender, 

 wavy filaments. 



Biological Characters. Does not grow in the ordinary culture media, 

 but may be cultivated in neutral rabbit bouillon ; a less favorable medium is 

 blood serum from the horse. When small fragments of the organs of an 

 infected animal are placed in rabbit bouillon they become enveloped, in the 

 course of three or four days, in a cotton-like mass of filaments ; later white 

 flocculi are distributed tlirough the medium, which consist of similar fila- 

 ments loosely interlaced. The filaments may present swellings here and 

 there, which are supposed to represent involution forms. 



Pathogenesis. Rabbits inoculated in the ear or in the anterior chamber 

 of the eye with the flocculi from a bouillon culture, or with a small frag- 

 ment of one of the organs of an infected animal, usually die at the end of 

 eight days. At the autopsy a necrotic, cheesy process is found at the point 

 of inoculation, and purulent foci, surrounded by inflamed or necrotic areas, 

 in the lungs ; also purulent collections in the myocardium ; these were the 

 principal pathological changes, but sometimes nodules were found in the 

 abdominal viscera. The slender bacilli described were found in all of these 

 localized centres of infection. Pathogenic also for white mice, which usually 

 died in six days after being inoculated subcutaneously. 



116. BACILLUS COPROGENES FCETIDUS. 



Synonym. Darmbacillus of Schottelius. 



Obtained by Schottelius (1885) from the intestinal contents of pigs which 

 had died of Schweiiierothlauf (rouget) . 

 35 



