OCCURRENCE AND PATHOGENESIS 205 



it sometimes forms pseudofilaments. It is pathogenic to mice, and 

 according to Rabe, also to guinea-pigs. 



STREPTOCOCCI IN OTHER DISEASES. 



Streptococci in Morbus Maculosus Equorum. The disease known as 

 morbus maculosus equorum, acute hemorrhagic anasarcous toxemia, 

 or petechial fever, occurs either sporadically or in epidemic form, 

 particularly after influenza and strangles. Ligniere, who investigated 

 the bacteriology, claims that he generally found the Streptococcus 

 pyogenes and more rarely the Streptococcus equi and the Bacillus 

 equisepticus in the blood of horses which had died from the disease. 

 However, neither Ligniere nor any other investigator has been able 

 to produce the disease experimentally by the inoculation of these 

 organisms. 



Streptococci in Contagious Pleuropneumonia of Horses. An organism 

 which presents itself as a diplococcus in tissues, but as a streptococcus 

 in pure cultures, was described as the cause of this disease by Schiitz 

 in 1887. It often shows a capsule in tissues, stains with the ordinary 

 watery anilin stains, but not by Gram's method. It grows on agar 

 and gelatin at room and incubator temperature, and Schiitz claims 

 that he has been able to produce the disease in horses by intrathoracic 

 injections of pure culture. According to Ligniere, Schutz's organism 

 is identical with the Streptococcus equi. 



Streptococci in Apoplectiform Septicemia in Chickens. Noergaard 

 and Mohler have described a streptococcus occurring in short or 

 long chains, with individual cocci 0.6 to 0.8 micron in diameter, as 

 the etiologic factor of this disease. The organism is Gram positive. 

 It grows in the presence or absence of oxygen. It forms flaky masses 

 in bouillon, and leaves the fluid clear, changes an alkaline medium to 

 an acid one, and does not liquefy gelatin. It does not greatly change 

 the appearance of milk, nor does it form a visible growth on potatoes. 

 It is fatal to fowls, mice, rabbits, and swine, but not to guinea-pigs, 

 dogs, and sheep. 



BOTRYOCOCCUS ASCOFORMANS. 



Occurrence and Pathogenesis. The organism, now generally known 

 as Botryococcus ascoformans, is the cause of a suppurative infection 

 known as botryomycosis. The clinical manifestations and histo- 

 pathology of the disease somewhat resemble actinomycosis, but the 

 causative organism is entirely distinct. While actinomycosis is com- 

 mon in cattle and rare in the horse, botryomycosis is common in the 

 horse and relatively rare in cattle. It is also occasionally seen in the 

 hog and in man. The disease is remarkable because it represents a 

 pathologic process showing some common features of an infectious 

 granulonia and of a true tumor. The botryomycotic new formations 



