318 TEXT-BOOK OF BACTERIOLOGY. 



tivate these micro-organisms in many cases. On the gelatin plate 

 and in the test-tube, the bacillus exhibits a pronounced similaritj' 

 with Friedlander's pneumococcus, except that the head of the nail- 

 shaped culture appears more transparent and milky than the thick, 

 white aggregation of a china lustre of the pneumococci. 



The bacteria thrive on agar, blood-serum, potatoes, and in bouil- 

 lon and form luxuriant colonies usually consisting of capsulated 

 rods in the solid media, while the gelatinous envelope fails to de- 

 velop in the nourishing fluid. 



Experiments with animals have shown that the bacilli possess 

 about the same pathogenic properties as the pneumococci. No 

 symptoms, however, resembling the picture of rhinoscleroma have 

 developed in connection with transmission, and it will be well to 

 refrain from any final decision regarding the specific signif- 

 icance of this micro-organism and to await the result of further 

 investigations. 



XIX. MICRO-ORGANISMS OP WOUND INFECTION. 



Eminent physicians have for a long time recognized that the 

 majority of processes retarding the healing of wounds must be 

 attributed to external influences and are caused by the access of for- 

 eign and injurious substances. A better insight into the signifi- 

 cance of the peculiar activity of micro-organisms removed any 

 doubt of their important character, and it was generally admitted 

 that the circumstances above mentioned owed their origin to some 

 infection. 



Lister succeeded in reaching these conclusions before they were 

 proven, and in thus removing the worst enemies of wound-repair. 

 Wherever these teachings are ignored, the bacteria raise their head 

 ominously and begin their fatal activity. 



The really severe wound-poisonings (such as hospital gangrene, 

 etc.) have nowadays nearly disappeared. Of the less dangerous 

 consequences, only erysipelas is still of frequent occurrence. Its 

 "traumatic form," caused by lesions, etc., was formerly distin- 

 guished from an " idiopathic " erysipelas regarded as a peculiar, 

 well-defined disease. But this distinction can no longer be main- 

 tained, as both forms have but one cause. 



Manj'^ observers had established the presence of micrococci in the 

 er^'sipelatous tissue, especially in the margins of the affected skin. 

 Fehleisen succeeded in growing these bacteria artificially outside 

 of the body, and by transmitting them to previously healthy peo- 

 ple, he reproduced a tj'pical erysipelas, thus proving conclusively 

 the specific significance of the micro-organisms. 



