38 OFFENSIVE FORCES OF INVADING MICROORGANISM 



are certain facts, however, which suggest that this explanation is 

 not correct. We find that capsule formation may be evoked by agents 

 which have no nutrient properties whatever. Danysz thus found that 

 the anthrax bacillus when grown in arsenical media of increasing 

 concentration forms enormous mucinous capsules which protect 

 the organism against the bactericidal action of the chemical in 

 question. 



Weil and Suzuki further found that certain sarcinse (i. e., absolute 

 saprophytes), when exposed to the action of leukocytes which readily 

 destroy them, undergo a peculiar mucinous degeneration which 

 in the beginning is directly comparable, if not identical with capsule 

 formation, but proceeds beyond this, and ends with the death of 

 the organism. In this case the capsule formation is evidence of a 

 serious impairment of the vitality of the cell and closely analogous 

 to the granular degeneration of vibrios under the influences of the 

 bactericidal substances of the serum. It does not necessarily follow 

 of course that capsule formation among the pathogenic parasitic 

 organisms should likewise be a degeneration phenomenon, but the 

 above observations suggest this possibility, and it will be well in 

 future investigations to take it into account. 



It is also quite in accord with the present tendency to regard 

 capsule formation as a pathological state on the part of the micro- 

 organisms that the anthrax bacillus never forms spores in the animal 

 body, no matter how extreme the infection may be. One would 

 accordingly expect that in a long-continued series of transplantations 

 from animal to animal the vitality of the microorganism would 

 finally be damaged so severely that a further transfer would not 

 lead to infection. This actually seems to be the case, for neither 

 Bail nor Gruber and Wiener were able to maintain an uninterrupted 

 series in the case of the anthrax bacillus on the one hand and the 

 cholera vibrio on the other. 



In this connection it is interesting to note that in especially severe 

 infections certain organisms, such as the anthrax and the Friedlander 

 bacillus, may appear capsule-free even in the infected body, which at 

 first sight is difficult to reconcile with the idea that capsule forma- 

 tion is essential to infection. The true significance of the phenomenon, 

 however, is suggested by the observation that in the test-tube experi- 

 ment a serum may be deprived of its power to elicit capsule formation, 

 if an abundant culture has once been raised from it, which seems to 



