. A text-book of bacteriology. Bacteriology. PYOGENIC BACTERIA. 383 genie for rabbits only. The author named, as a result of extended and carefully conducted comparative studies, arrives at the following conclusions: " According to my observations, there are two great groups among the streptococci. These cannot be distinguished one from the other in cultures in highly albuminous media (pus, blood serum), but present constant dif- ferences when cultivated in bouillon. The decisive characteristics in this medium are : macroscopic, the cloudiness of the medium ; microscopic, the length of th
. A text-book of bacteriology. Bacteriology. PYOGENIC BACTERIA. 383 genie for rabbits only. The author named, as a result of extended and carefully conducted comparative studies, arrives at the following conclusions: " According to my observations, there are two great groups among the streptococci. These cannot be distinguished one from the other in cultures in highly albuminous media (pus, blood serum), but present constant dif- ferences when cultivated in bouillon. The decisive characteristics in this medium are : macroscopic, the cloudiness of the medium ; microscopic, the length of the chains. The two groups are with difficulty distinguished in agar cultures; more easily in gelatin, in which the streptococcus which forms short chains causes a slight liquefaction, while the Streptococcus longus does not. Upon potato Streptococcus brevis alone shows a visible growth. . We see here a group of streptococci which we separate from the others, because of their microscopic and cultural differences, under the name of Streptococcus brevis, which is also distinguished by having no pathogenic action upon the animals usually experimented upon. We recognize, on the other hand, the streptococci which we have grouped to- gether as Streptococcus longus as all pathogenic and about in equal degree for a certain species of animal (rabbits); but by experiments upon other species (mice) we arrive at the conclusion that there must also be differences between these streptococci. It appears that the streptococci which are dis- tinguished by their high degree of pathogenic power upon mice are also those which are distinguished in bouillon cultures by the formation of con- glomerate masses. We find among these also one which is distinguished by especial virulence for mice, and that this one is distinguished in cultures by its scanty growth upon ox ; The more recent researches of Knorr (1893), and of Waldvogel (1894), indicate that the classification of the streptococci pro
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectbacteri, bookyear1901
