388 BACTERIA IN MILK 



coccus laciiciis. His conclusions were soon well supported by the investigations of 

 Holling' and Heinemann.^ Lehmann and Neumann^ accepted this conclusion but, be- 

 cause the name that they had previously given had priority, changed their name to 

 Streptococcus giintheri, and later, as already indicated, decided to accept Grotenfelt's 

 still earlier Streptococcus acidi lactici. Sewerin^ a few years later carelessly used the 

 name Bacillus lactis acidi, which Leichmann had proposed for long-rod bacilli, for 

 this organism, thus adding to the synonomy. 



All of this confusion has been cleared up by the suggestion made by Lohnis^ in 

 1909 that we should return to Lister's original specific name lactis but place the or- 

 ganism in the genus Streptococcus as Kruse had indicated. This practical suggestion 

 met with opposition from Wolff,*" who had another name to propose, Bacterium leich- 

 manni, and Kruse^ and some others who feel that Lister's original descriptions are too 

 indefinite to be accepted. Nevertheless, the majority of the dairy bacteriologists of 

 Europe and America are already using this binomial; and there is so much that can be 

 said in favor of using this simple and expressive name that it is hoped that it will 

 receive general international approval and use. 



A few bacteriologists — e.g., Heim^ — not familiar with recommended forms of 

 nomenclatural usage, have written the binomial Streptococcus lactis Lister instead of 

 Lohnis. This is incorrect as it indicates that Lister used this particular binomial, 

 whereas even the thought of the generic name Streptococcus quite certainly never 

 entered his mind. The term S. lactis is also occasionally incorrectly ascribed to Heim. 



It has been difficult to determine the natural habitat of this streptococcus. No 

 better summary of the matter can be given than to quote Lister's original remark that 

 reads as follows: "But though the ferment which occasions the souring of milk is 

 present in milk obtained from any dairy, it appears to be by no means common in the 

 world in general." As investigations have been made, it has been discovered that 

 streptococci found in the cow's and in the human mouth, and in cow's and human feces 

 {Enterococcus) , all show characters almost identical with those of .5. lactis so that 

 some have held these habitats to be the original sources of this organism, while others 

 have held that the organisms found in these habitats are closely related to, but not 

 identical with, .S". lactis. The matter of these relationships is well summarized in recent 

 papers by Ayers, Johnson, and Mudge.^ The organisms as they appear in milk show 

 certain definite varieties, i.e., slimy, heat resistant, slow reducing, slow coagulating, 

 and caramel or burnt flavor. Some would regard these as distinct species. They are 

 well described and characterized by Hammer and Baker.'" 



' Holling, A.: Inaug. Diss. Bonn, 1904; Abstract in Centralbl.f. Bakteriol., Abt. I, Ref., 36, 659. 

 1905. 



' Heinemann, P. G. : J. Infect. Dis., 3, 173. 1906. 



3 Lehmann, K. B., and Neumann, R. O.: op. cil. (2 vols.; 4th ed.), Munich, 1904. 

 * Sewerin, S. A.: Centralbl. f. Bakteriol., Abt. II, 22, 3. 1908. 

 sLohnis, F.: ibid., p. 553. 1909. '■WoHT, A.: ibid., 24, 55. 1909. 



7 Kruse, W.: Allgemeine Mikrobiologie. Leipzig, 19 10. 

 'Helm, L.: Ztschr.f. Hyg. u. Injektionskrankh., loi, 104. 1923. 

 9 Ayers, S. IL, Johnson, W. T., and Mudge, C: /. Infect. Dis., 34, 29, 49. 1924. 

 '" Hammer, B. \V., and Baker, M. I'.: Iowa .igric. Expcr. Sta. (.lines) Research Bull. gg. 1926. 



