30 H. L. Russell. 



A marked increase with B. megaterium, B. butyricus, B. coli 

 commune and B. pyocyaneus was noted, while Strept. pyogenes in 

 five days was killed. As the death of the bacteria inoculated did 

 not occur at once, but was gradual, it was no doubt due to unfav- 

 orable nutritive conditions rather than any germicidal effect of the 

 cell fluids. 



The cell sap usually possesses a distinct acid reaction, and would,, 

 no doubt, inhibit the growth or kill out by malnutrition those forms 

 susceptible to acid reaction. Some plant-juices afford a much better 

 nutritive medium than others, such as the sugar-cane or the saccha- 

 rine varieties of sorghum, or the sap of such trees as Acer sacchari- 

 num. Sternberg 1 has recommended the milk in green cocoanuts as a 

 nutritive medium for even animal pathogenic organisms. This i& 

 really the elaborated cell sap of the embryo-sac. 



In the animal body we find that a bactericidal property is not 

 only resident in the blood plasma and tissue juices, but is also found 

 in various secretions and excretions which are formed in the animal 

 organism. 



Thus the sputum of a healthy individual is known to have an 

 anti-bacterial effect on anthrax, 2 while the germicidal properties of 

 fresh milk 8 and urine 4 are quite considerable. 



Although we have been unable to detect any analogous property 

 in the cell sap of the plant, we know that the plant is able in many 

 cases to protect itself by means of its secretions. Thus conifers are 

 protected from disease in many cases by the copious flow of turpen- 

 tine, which forms an effectual barrier against the entrance of fungi as 

 well as bacteria. 5 The ethereal oils which are found so widely 

 distributed throughout the plant kingdom are known to possess 

 the ability of hindering, and in many cases actually destroying, 

 germs when brought in contact with them. 6 In all probability they 

 function in a similar way in the plant, although many parasites may 

 have adapted themselves to this condition. 



1 Sternberg : Phil. Med. News, 1890, p. 262. 

 2 Nuttall: Boylston Essay, Harvard, 1888. 



3 Fokker: Zeit. f. Hyg., IX (1890), 41. 



4 Lehmann: Cent. f. Bakt. VII (1890), 457. 

 6 Hartig: Die Baumkrankheiten, S. 139, 166. 



6 Cadeac et Meunier : Ann. de PInst. Past. 1889, 317. Freudenreich : Ann. de 

 Microg., 1889. 



