390 BACTERIA IN MILK 



tici lb"!! Grotenfelt, 1889, p. 1 23) ; Bacterium acidi lactici Migula, 1895, p. 25 (Not Bacterium 

 acidi lactici Kruse, 1896, p. 357, the "Bacterium B" of Peters, 1889, p. 422); Possibly also 

 Bacterium grotenfcldtii Migula, 1900, p. 408, a synonym of Bacterium acidi lactici I Groten- 

 felt; ? Bacillus lacticus Pasteur according to Mace, 1913, II, p. 452 (Not Bacillus lacticus Kruse, 

 1896, p. 356); Bacterium duodenale Ford, 1903, p. 17 (according to Perkins, 1925, p. 247); 

 Encapsulatus acidi lactici Castellani and Chalmers, 1919, p. 934; (Encapsulata) Bacillus 

 duodenale Perkins, 1925. p. 247. 



Aerobacter aerogenes (Kruse) Beijerinck,' 1900, p. i 

 Synonyms: Bakterium lactis aerogenes Escherich, 1885, p. 520; Bacterium lactis Baginsky, 

 1888, p. 437; Bacterium aceticum Baginsky, 1888, p. 462; Bacillus lactantium Trevisan, 1889, 

 p. 15; Bacillus lactis aerogenes Sternberg, 1893, p. 447; Bacillus aerogenes Kruse, 1896, p. 340 

 (Not Bacillus aerogenes Miller, 1886, p. 119); Bacterium aerogenes Chester, 1897, p. 78, and 

 Bacterium aerogenes Migula, 1900, p. 396 (Not Bacterium aerogenes Miller, 1886, p. 119); 

 Encapsulatus lactis aerogenes Castellani and Chalmers, 1919, p. 934; (Encapsulata) Bacillus 

 aerogenes Perkins, 1925, p. 254. 



The history of these two micro-organisms has been interwoven from the time 

 when Escherich^ stated in his description of Bakterium lactis aerogenes that this organ- 

 ism showed only minor differences from Hueppe's previously described Milchsaure- 

 bacterium. Because of this suggestion, many bacteriologists have regarded the two or- 

 ganisms as identical, the two being given as synonyms even in the latest edition of 

 Lehmann and Neumann's well-known Manual, and in other recent publications by 

 European bacteriologists. 



Both Escherich and Hueppe report their organisms as non-motile, while Bacte- 

 rium coli commune Escherich was motile. In the original description both of the non- 

 motile organisms were described as forming spores; but there is reason for believing 

 this was a mistake in both cases. During the same period Gaffky described spores for 

 the typhoid organism, spores were described for the blue-milk organism, and other 

 rod-shaped bacteria were generally believed to form spores if grown on suitable media, 

 Migula, using a quince-slime medium, thought he found spores in so many bacteria 

 that he regarded spore formation as such a difficult and uncertain character to de- 

 termine that he used motility rather than spore formation to separate the genus Ba- 

 cillus from Bacterium. 



Both Escherich and Gaflky later admitted that they were mistaken. While no 

 record has been found that Hueppe did the same, it is worth noting that Grotenfelt,^ 

 a student of Hueppe's who used one of Hueppe's cultures, makes no mention of spores, 

 and all later workers who studied probably authentic cultures supplied by Krai or 

 from Koch's laboratory report Hueppe's organism as a non-spore-former. Lehmann 

 and Neumann^ state that Migula's deception arose from the fact that spores were al- 

 ready present in the quince slime when it was prepared. In other cases it may be that 

 these reports were caused by contaminated cultures, unstained vacuoles, the presence 

 of swollen tips of pleomorphic forms combined with the uncritical practice of the pe- 



' Beijerinck, M. W.: op. cit., 4, i~iS; Cenlralbl. f. Baktcriol., Abt. II, 6, 193. 1900. 

 ^Escherich, T.: Fortschr. d. Med., 3, 515. 1SS5; Darmbakterien des SiiitgUngs. Stuttgart, 1SS6. 

 3 Grotenfelt, G.: Fortschr. d. Med., 7, 121. 1889. 

 ■< Lehmann, K. B., and Neumann, R. O.: op. cit. (5th ed.), p. 155. Munich, 1912. 



