( 337 ) 



serum prepared bj himself. This serum was obtained from a horse, 

 which foi- some time was injected intravenously with a mixture of 

 6 — 8 different streptococci, which but for one exception originated 

 immediately, so, without passage through animals, from pathological 

 processes of man. Besides, he has made use of the presence of an 

 amboceptor in his serum to investigate, whether it might be possible 

 to separate different races of streptococci from each other with the 

 aid of this substance. 



Among the principal difficulties, which are still experienced in the 

 preparation of an anti-streptococcus serum, must be mentioned in the 

 first place, that the streptococci proceeding directly from patholo- 

 gical processes of man and being very virulent for him (scarlatina, 

 erysipelas, septicemia etc.) possess in general for our common test- 

 animals a comparatively small degree of virulency. By this the pre- 

 paration of a very powerful serum is somewhat impeded and on the 

 other hand it is almost impossible to controll the obtained serum. 

 In the second place the question prevails, whether all streptococci, 

 cultivated from diflterent processes of disease, must be regarded as 

 representatives of one and the same species, and to be taken as 

 varieties, or that the mutual affinity is much smaller. A solution of 

 this question in such a sense, that it might be possible to come to 

 a rational sub-division in the large group of the pathogenic strepto- 

 cocci, would be of great importance for the bloodserum-therapy. 



Some years ago Schottmüller ^) tried to give a new division, based 

 on biological grounds instead of the older morphological division in 

 streptococcus longus and streptococcus brevis (von Lingelsheim "), 

 Behring ^). By cultivating different races of streptococci on blood- 

 agar, he was enabled to discern two types : firstly dark grey 

 colonies with lucid area, secondly greenish ones without area. The 

 streptococci, belonging to the first group, are very virulent for man and 

 are found in erysipelas, septicemia, scarlatina, phlegmon etc., while 

 those, belonging to the second group, are generally less pathogenic 

 for man and animals. Therefore Schottmüller divides the pathogenic 

 streptococci as follows: 



1. Streptococcus pyogenes s. erysipelatos. 



2. Streptococcus mitior s. viridans. 



3. Streptococcus mucosus. 



Several other investigators (Eug. Fraenkel *), Silberstrom *), 



1) Munch. Med. Wochenschrift, 1903, No. 20, S. 849; No. 21, S. 909. 



2) Zeitschrift fur Hygiene, Bd. X, S. 331. 



8) Gentralblatt. fur Bakteriologie, Bd. 12, S. 192. 



4) Munch. Med. Wochenschrift, 1905, N'\ 12, S. 548; m 39, S. 1869. 



5) Gentralblatt fur Bakt., le Abth., Orig., Bd. 41, S. 409. 



