COCCACE^ AND THEIR PARASITIC RELATIONSHIPS 273 



the bottom . of the tube. Various carbohydrates are fermented 

 with the production of add and without formation of gas, but 

 the behavior of streptococci toward these substances seems so 

 variable that the attempts to utilize the fermentative power as 

 a basis for classifying the streptococci has not led to wholly satis- 

 factory results. The differences in fermentative power seem to 

 depend more upon vigor of growth than upon essential qualita- 

 tive differences between the streptococci tested.^ 



The streptococcus is relatively very resistant to heat, at times 

 requiring one to two hours heating at 65° C. or one hour at 70° 

 C. in order to insure sterility, according to V. Lingelsheim. Most 

 investigators have found 60° C. for twenty minutes sufficient. 

 Its poisons seem to be chiefly intracellular and set free upon dis- 

 integration of the organisms. Soluble poisons have nevertheless 

 been found in some cultures. 



Laboratory animals are not very susceptible to inoculation 

 with streptococci. White mice and rabbits are most useful, 

 and tbey ordinarily Succumb to intraperitoneal injection of. 

 virulent strains. 



The enormous importance of the streptococcus as a cause 

 of sickness and death before the aseptic era is difficult to realize 

 at the present time. Veritable epidemics of streptococcus in- 

 fection in the surgical and obstetrical wards of hospitals made 

 this one of the most dreaded of diseases. Even to-day the 

 virulent streptococcus is held in great respect by many surgeons, 

 and cases of erysipelas and other recognizable active streptococcus 

 infections are commonly excluded from surgical wards. 



In war wounds the streptococcus is a common and serious 

 infectious agent. Its presence may be rapidly detected by in- 

 oculating the wound exudate into broth containing a bit of liver 

 or other tissue. 



Erysipelas is an acute febrile disease characterized by a local 

 redness and edema of the skin which tends to spread to contigu- 

 ous areas. In the lymph spaces beneath the epithelium there is a 



' V. Lingelsheim in KoUe und Wassermann, Handbuch, igizj Bd. IV, S. 462. 

 IS 



