156 SUPPURATION AND ALLIED CONDITIONS. 



cannot be maintained, and now nearly all authorities are 

 agreed that the two organisms are one and the same, 

 erysipelas being produced when the streptococcus pyogenes 

 of a certain standard of virulence gains entrance to the 

 lymphatics of the skin. 



Petruschky in a recent publication (1896) has shown 

 conclusively that a streptococcus cultivated from pus may 

 cause erysipelas in the human subject. He obtained a pure 

 culture of a streptococcus from a case of purulent peritonitis 

 secondary to parametritis, the patient never having suffered 

 from erysipelas. By inoculations with this culture he pro- 

 duced typical erysipelas in two women suffering from cancer. 



More recently a distinction has been drawn between a streptococcus 

 longus, which corresponds to the streptococcus pyogenes, as it usually 

 forms long chains, and is pathogenic to rabbits or mice, and a strepto- 

 coccus brevis, which occurs in the mouth in normal conditions and 

 is without pathogenic properties when tested experimentally. The 

 growth of the former in bouillon forms a somewhat granular deposit, 

 that of the latter a more abundant and flocculent deposit. Marmorek 

 has, however, found that the same streptococcus may at one time grow 

 in short, at another in long chains, and Kolle has shown that a strepto- 

 coccus, which originally grew in long chains, formed only short chains 

 after being repeatedly passed through the body of the mouse, and the 

 appearance of the growth in bouillon was correspondingly altered. 

 Further, Widal and Bezan^on found that a streptococcus cultivated 

 from the mouth and which was non-pathogenic, became pathogenic when 

 inoculated along with the bacillus coli communis, and thereafter its 

 virulence could be enormously increased by passing it through a series of 

 animals. These latter observers also found that streptococci cultivated 

 from the mouth of a smallpox patient were non-virulent, whilst those 

 cultivated from the blood of the same patient post mortem were highly 

 virulent, the probability being that those in the blood had been 

 derived from those in the throat. There does not therefore seem at 

 present sufficient evidence for looking upon these two varieties as 

 distinct species. It is sufficient to bear in mind that streptococci in 

 the normal mouth are usually non-virulent, and grow in short chains. 

 On the other hand, in some cases of very virulent streptococcus infec- 

 tion in the human subject we have found the organism occurring only 

 in very short chains. The streptococcus conglomerates , so called from 

 the appearance of the growth in bouillon, is to be regarded merely as 

 another variety, which forms very long chains and is usually possessed 

 of a high degree of virulence, though its distinctive characters are not 

 permanent. It has often been obtained from the fauces in scarlet fever. 



