3CXI] PATHOGENIC ORGANISMS 567 



be the primary and essential part to which the resistance and 

 immunity of the tissue or the animaHs are due. This does not 

 deny the possibility that leucocytes do and can take up 

 microbes still in a living and even active state, but, what 

 seems from all that has been said highly improbable, that such 

 phagocytosis is the first phenomenon in the destruction and 

 neutralisation of the microbes introduced into a tissue, or 

 that it is sufficiently extensive or sufficiently early to account 

 for the rapid and complete destruction of the microbes intro- 

 duced that in some cases is noticeable. This forces us to 

 assume that spontaneous resistance or immunity is primarily 

 and essentially due to an inimical action of the blood and 

 tissue or tissues per se on the microbe, a view which as we 

 shall see harmonises well not only with the facts concerning 

 natural immunity, but in a still more marked manner with 

 acquired, active, or artificially produced immunity. 



The first definite proof as to the germicidal power of 

 blood was given by Fodor {Deutsche med. Wochenschrift, 

 1887, No. 34), then Nutall {Zeitschrift f. Hygiene, 1888, iv. 

 p. 353), Niessen (Zeitschr. f. Hygiene, 1889, vi. p. 487), 

 Behring {CentralbL f. Klin. Med. 1888, No. 38), and par- 

 ticularly Buchner (Centralbl. f. Bakt. n. Farasit., 1889, 

 vol. V. p. 25, vol. vi. pp. 14, 21 ; Archiv f. Hygiene, 1890, 

 p. 85), and others have shown that the plasmatic fluids of 

 the body — lymph and blood — have in their fresh and living 

 state the power to destroy and kill bacteria brought into 

 contact with them. The experiments of Buchner, Nutall, 

 and Niessen have shown that the fresh blood plasma used 

 in the test-tube has a remarkable power of doing this, 

 although this power differs considerably as regards different 

 species. Thus, micrococcus aquatilis, cholera spirillum, 

 anthrax bacillus, typhoid bacillus, and the bacillus of Fried- 

 lander are easily killed after a few minutes (five to twenty 



