THE VITAL PROPERTIES OF THE CELL 123 



tive proportions of the stimulating substance which is present in 

 each region. 



The numerous possibilities may be grouped under two heads. 



First group. The metabolic products are evenly distributed or 

 approximately so throughout the blood and the diseased tissues. 

 Since under these conditions there can be no special point of 

 stimulation, it stands to reason that the leucocytes cannot wander 

 away from the diseased spot. 



Second group. The collections of products are unequal in con- 

 centration, and further, the difference in their concentration is 

 sufficient to give rise to an effective stimulation. Two alter- 

 natives may occur. Either the higher degree of concentration is 

 present at the seat of the disease, or in the blood-vessels. In the 

 first case only will the leucocytes collect around the affected 

 tissue. 



The consideration of these relative conditions appears to me to 

 explain many interesting phenomena, which have been observed 

 by certain French investigators, Roger, Charrin, Bouchard (IV. 

 Ib), etc., during their various experiments with the catabolic 

 products of the Bacillus pyocyaneu.s, of the Anthrax bacillus, etc. ; 

 and by Koch in his observations upon the action of Tuberculin. 

 I have endeavoured to explain such phenomena in a short popular 

 paper : " Ueber die physiologische Grundlage der Tuberculin 

 wirkung, eine Theorie der Wirkungsweise bacillarer Stoffwechsel- 

 producte" (IV. 13), to which I refer the reader for information 

 with regard to physiological experiments and the explanation of 

 the special phenomena of disease. 



Literature IV. 



!A. CLAUDE BERNARD. Legons sur les phenomenes de la vie commune aui 



animaux et aux vegetaux. 



IB. BOUCHARD. Theorie de Vinfection. Verhandl. des X. intern, med. Con- 

 gresses za Berlin. Bd. I. 1891. 



2. BUCHNER. Die chemische Eeizbarkeit der Leukocyten und deren Beziehung 



zur Entzundung und Eiterung. Berliner klinische Wocheschn. 1890. 



3. BRUCKE. Untersuchungen iiber den Farbenwechsel des afrikan. Chameleons. 



Denkschrift d. math, nakuru)., Clause der Akad. d. Wissensch. Bd. IV. 

 1854. 



T. LAUDER BRUNTON. Action of Drugs on Protoplasm. Pharmacology 

 Therapeutics and Materia Hedica. London. 



4. BUNGE. Vitalismus und Mechanismus. 



5A. DE BARY. Voiiesunfjen iiber Bacterien. 1885. 



