528 



BACTERIOLOGY. 



a variety of channels, and thus serve as a source of 

 further dissemination of the disease. 



The organism was first observed by Feser, and subse- 

 quently by Bollinger and others. The most complete 

 description of its morphological and biological peculi- 

 arities is that of Kitasato.' The following is from 

 Kitasato's contributions : it is an actively motile rod 

 about 3 to 5 /^ long by 0.5 to 0.6 fi thick. It has 

 rounded ends, and, as a rule, is seen singly, though 

 now and then pairs joined end to end may occur. It 

 has no tendency to form very long threads. (Fig. 100, A.) 



It forms spores, and when in this stage is seen to be 



Pig. 100. 



Bacillus of symptomatic anthrax, a. Vegetative stage— gelatin culture. 

 B. Spore-forms— agar-agar culture. 



slightly swollen at or near one of its poles, the loca- 

 tion in which the spore usually appears. (Fig. 100, B.) 

 It is markedly prone to undergo degenerative changes, 

 and involution-forms are commonly seen, not only in 



1 Zeitsohrift fiir Hygiene, Bd. vi. S. 105 ; Bd. viii. S. 55. 



