276 A MANUAL OF BACTERIOLOGY 



times as secondary invasions at autopsies), and Birge x 

 has isolated a similar but less virulent organism from the 

 larynx of crows. Braxton Hicks 2 has also isolated this 

 organism from a case of malignant endocarditis. 



Micrococcus neoformans 



This organism was isolated by Doyen from malignant 

 growths, and was supposed by him to be the causative 

 organism of malignant disease. It is a typical Gram- 

 positive coccus, giving a white growth on agar and liquefy- 

 ing gelatin in three to four days. According to Dudgeon 

 and Dunkley, 3 it gives all Gordon's fermentation tests 

 for the M. pyogenes, var. albus, except that it does not 

 acidify mannitol. 



The serum of patients suffering from malignant disease does 

 not give any marked agglutination with the M. neoformans, nor 

 does it contain opsonins specific for the organism. The M. 

 neoformans is non-pathogenic for rats and mice. 



Botryomycosis 



This condition is met with in the horse in the form 

 of fibroid granulomata in the organs and in the abdomen, 

 which may break down and discharge a yellowish pus. 

 Groups of micrococci embedded in a gelatinous matrix 

 are present in the granulomata and in the pus (Ascococcus 

 equi). 



The Streptococci 



Many streptococci of very variable virulence and 

 biological characters occur in man and animals. Formerly 

 only one pathogenic species was described, Streptococcus 



1 Johns Hopkins Hosp. Bull, vol. xvi, 1905, p. 309. 



2 Trans. Roy. Soc. Med., vol. v, 1912, Path. Sect., p. 126. 



3 Journ. of Hygiene, vol. vii, 1907, p. 13. 



