200 A MANUAL OF BACTEKIOLOGY 



germicidal constituents of the cells and body fluids Buchner 

 gave the name " alexins." 



Grohmann performed the first experiments with extra- 

 vascular blood. He found that anthrax bacilli, after being 

 kept in plasma, became less virulent. Fodor, adding 

 anthrax bacilli to blood and plating at intervals, found 

 there was a progressive diminution in the number of 

 organisms. 



Nuttall, in 1888, used the defibrinated blood of several 

 animals, rabbits, mice, pigeons, sheep, and found that it 

 destroyed the B. anthracis, B. subtilis, B. megaterium, and 

 M. pyogenes var. aureus. He confirmed Fodor's results, 

 which also showed that after a while the blood loses its 

 germicidal properties and becomes a suitable culture 

 medium. The blood or serum similarly loses its bactericidal 

 properties on heating, and serum that has once been used 

 loses its bactericidal properties. Nissen continued this 

 work, and also found that fresh serum is germicidal for a 

 variety of organisms. 



In 1890, Buchner with Voit, Sittmann, and Orthen- 

 berger came to the conclusion that the germicidal action 

 of cell-free serum is due to the protein constituents. 



Christmas prepared a germicidal substance from the 

 spleen, and Bitter, who examined the method, in the main 

 confirmed Christmas. 



Behring and Nissen, however, found that the serum 

 of the white rat, dog, and rabbit destroys the Bacillus 

 anthracis, but serum from the mouse, sheep, guinea-pig, 

 chicken, pigeon, and frog has no action. Thus, while the 

 rabbit is highly susceptible to anthrax, its serum is germi- 

 cidal ; the chicken, on the other hand, is immune to 

 anthrax, but its serum is inactive. Hence there is a 

 considerable difference between the action of circulating 

 and of extra-vascular blood. 



Vaughan, Novy and McClintock, in a series of papers, 



