ROBERT S. BREED 385 



potato to dust contaminations, and Koch' was laboriously preserving pure cultures of 

 the anthrax organism by passage through mice. 



Lister's iinal descriptions of the sour-milk organism are so complete and his studies 

 of its habitat so accurate that it is evident that he was dealing with the organism that 

 is most commonly found in sour milk. A sentence taken from one of his papers^ pub- 

 lished in 1S78 (p. 437) will show this: "The organism is a motionless bacterium, that 

 is to say, exhibiting no movement except a slight jogging, occurring most commonly 

 in pairs, but frequently in chains of three, four or more individuals, each segment 

 being of somewhat rounded form, more or less oval, with the long diameter in the di- 

 rection of the length of the chain, and often showing, on careful focusing, a line across 

 the central part indicating transverse segmentation." He adds the following illumi- 

 nating footnote: "In giving these as the characters of the Bacterium laciis, I do not 

 wish to be understood as stating that this species can always be certainly recognized 

 by its morphological features alone." 



Fortunately, Lister did his work at ordinary room temperatures, and thereby 

 avoided the pitfall into which Hueppe^ fell. Because the latter followed the normal 

 practice in a laboratory dealing with pathogenic organisms and incubated his milk 

 samples at body temperature, he came to regard a short rod bacterium which curdled 

 the milk with extrusion of whey and with the formation of gas bubbles as the organism 

 that caused the normal souring of milk. He utilized the new gelatin-plating technique 

 of his time to isolate pure cultures and quite naturally isolated the common and well 

 developed colonies. In gelatin stabs these organisms grew well along the length of the 

 stab and also on the surface at the point of puncture. 



Hueppe reported this as a spore-former, an observation in which he was un- 

 doubtedly mistaken, as will be shown later (p. 390). In all his papers he spoke of his 

 organism as the Milchsaurebacterium, but Zopf^ and others soon gave it the name 5a- 

 cillus acidi lactici. For some years after this, confusion reigned because this new or- 

 ganism was regarded by many as the organism causing the normal souring of milk. 

 There was much discussion over the problem as to whether there was more than one 

 organism that could cause lactic acid fermentation. Hueppe's findings indicated that 

 several types of bacteria were concerned in this fermentation, and his conclusions 

 were soon confirmed by Marpmann,^ Grotenfelt,'' and others. It is difficult to deter- 

 mine what organisms were really studied by these investigators, expecially those 

 studied by Marpmann, for his descriptions were indefinite and his cultures were not 

 preserved and studied later by improved technique as were Hueppe's cultures. The 

 names that Marpmann introduced {Bacillus lactis acidi, Bacterium lactis acidi, Micro- 

 coccus lactis acidi, and Sphaerococcus lactis acidi) were likewise destined to increase the 

 confusion, and they have fallen into disuse. 



The work by Grotenfelt in 1889 is important as it was done under Hueppe's super- 



■ Koch, R.: ibid., 2, Heft 2, 277. 1876. 



^^ Lister, J.: Tr. Path. Soc, London, 29, 425. 187S. 



3 Hueppe, F.: Mitt. d. kais., Gesiindheilamle, Berlin, 2, 309. 1884. 



^Zopf, W.: Die Spaltpihe (sded.). 1S85. 



5 Marpmann, G.: Ergdnznngshefte Centralbl.f. allgem. Gesundheilspflege, 2, 117. 1886. 



* Grotenfelt, G.: Forlschr. d. Med., 7, 121. 1889. 



