b DR. E. KLEIN. 



[I am acquainted with Dr. Greenfield's paper on cultivations 

 of the Bacillus anthracis communicated to the Royal 

 Society on June ITth, 1880 ; but I am unable to find in it any- 

 thing to which I can attach importance, with the exception of 

 some observations that repeat earlier experiments of Dr. 

 Burdon-Sanderson and of Dr. Buchner. In my opinion some 

 of Dr. Greenfield's observations contain internal evidence that 

 he was occasionally operating with some harmless bacillus and 

 not with anthrax bacillus at all ; and I cannot admit his 

 claim to speak with authority on the etiology of splenic fever. 

 It may be noticed in this connection that Koch, in his last 

 elaborate paper on the subject, has not made a single mention 

 of Dr. Greenfield's assertions.] 



Buchner noticed, as his cultivations rose in degree of genera- 

 tion, that the bacilli showed a change in their general mode of 

 growth, inasmuch as, unlike their previous behaviour so often 

 described by Pasteur, Koch, and others, they ceased to form 

 the beautiful cloudy and flaky felt-work (Pasteur's " en fila- 

 ments tout enchevetres, cotonneux "j rising from the bottom of 

 the culture-vessel into the otherwise perfectly clear nourishing 

 fluid, but they gradually assumed the tendency to adhere to the 

 walls of the vessel. After a duration of cultivation of ninety 

 days (Buchner calls this the 900th generation), this condition 

 became very pronounced, and in later generations the bacilli 

 formed the same pellicle on the surface as do the harmless hay 

 bacilli. On changing the mode of growth he ultimately suc- 

 ceeded in obtaining bacilli that in this respect did not differ 

 from the typical hay bacilli. With reference to this point I 

 am inclined to think that Koch (* Aetiologie d. Milzbr.,' p. 22) 

 is right in refusing to accept this as proven ; he says that 

 Buchner had not sufficiently guarded himself against outside 

 contamination, and therefore it is quite possible that he intro- 

 duced into his cultivations at one or another step a common 

 bacillus which after several cultivations became so numerous 

 as to replace altogether the original Bacillus anthracis. 



With reference to Buchner's cultivations, by which (using 

 blood for his nourishing fluid) he gradually changed the 



