STREPTOTHRIX CAPR& 403 



have a greenish and dusted appearance; they are not moistened by 

 water which runs off as from a fatty substance. The organism grows 

 best in alkaline or neutral bouillon; a very slight acidity, however, 

 does not inhibit development; the reaction of the medium is not 

 changed. On agar there develop small, round, opaque colonies with 

 thickened margins and an uneven surface, which later looks as if 

 dusted over. Finally the surface becomes covered with a thick, 

 uneven layer. 



The appearance on coagulated blood serum resembles that on agar. 

 The growth, however, is not so rapid. On potatoes dry, uneven, pale 

 yellow colonies, with elevated margins, are formed. The organism 

 grows in milk, but neither produces acid nor coagulates it. The 

 organism is fairly resistant; it is killed after an exposure of ten 

 minutes to 70 C. When inoculated intraperitoneally into guinea-pigs 

 ^t produces pseudotuberculous lesions; subcutaneous inoculations 

 into cattle and sheep produce lesions like those of farcy found under 

 natural conditions. According to Nocard's experiments, rabbits, dogs, 

 cats, and equines are not susceptible to the Streptothrix farcinica. 



Streptothrix Canis. A number of cases of pleuritis and peritonitis 

 with slight elevation of temperature and the formation of a reddish- 

 brown, cloudy exudate in which white granules can be seen with the 

 naked eye have been observed in dogs. The pleura and peritoneum 

 are sometimes studded with fibrous appendages or villi, while the 

 lungs may contain hard, gray nodules of the size of a pea. In the 

 exudate and the tissue lesions conglomerations of slender filaments 

 are found. The organism has been studied by Bahr. The Strepto- 

 thrix filaments can be stained by Grain's method and sometimes 

 show club-like swellings at their free ends. The Streptothrix canis, 

 as it has been called, grows on artificial culture media at incubator 

 temperature, first only aerobically, later also anaerobically. In the 

 depth of the agar mulberry-like colonies composed of long, dividing 

 filaments, sometimes thicker at the ends are formed after three or four 

 days; threads broken up into segments are likewise seen. Pure 

 cultures inoculated intraperitoneally into mice produce purulent 

 abscesses. Rabbits infected subcutaneously develop nodules up to the 

 size of a hazelnut. Dogs can also be infected subcutaneously, and 

 the Streptothrix is found in the nodules and abscesses which develop. 



Actinomyces Bicolor. Another Streptothrix has been found in a case 

 of multiple brain abscesses in a dog. From the pus Trolldenier 

 obtained in pure cultures a Streptothrix or actinomyces which formed 

 on agar colonies which were yellow in the centre and white at the 

 periphery. The organism which proved pathogenic for mice, guinea- 

 pigs, rabbits, and dogs was called Actinomyces bicolor. 



Streptothrix Caprae. In a goat suffering from a pseudotubercular 

 affection of the lungs Zschokke found a Streptothrix which was not 

 only Gram positive but also acid fast. The organism was more 

 thoroughly studied by Silberschmidt, who ascribed the following 



