196 
but do not as a rule produce indol. Although known since Hueppe’s 
description as the Bacterium acidi lactici this organism is more com- 
monly called Bacterium xrogenes. 
The second group includes bacteria described by Clauss (loc. cit.), 
Gunther and Thierfelder, a Esten, * 6 Leichmann, c Kozai/ Schier- 
beck/ Haschmioto/ Harrison and CummingA Conn and Esten,* 
Holling/ and Utz/ The characteristic organism is defined as oval 
or lance shape, occurring in pairs or short chains, colored by Gram, 
growing slowly on ordinary media, and producing no gas in presence 
of sugars. The growth on solid media is delicate and translucent. It 
causes rapid acid fermentation of milk, with coagulation. Bac- 
terium lactis acidi, Bacterium acidi lactici, and Bacterium Guntheri 
are some of the terms used to designate this organism. 
The third group includes micrococci described by Grotenfeld (loc. 
cit.) and Weigemann (loc. cit.) as streptococci. The cultural char- 
acters of this group are exactly similar to those of the second, the 
sole difference in the descriptions being in the morphology, in one 
case an oval or lance-shaped bacillus, in the other a streptococcus. 
Kruse* in 1903 pointed out the close similarity of organisms classed 
in the second and third groups and suggested that the difference of 
morphology was merely one of interpretation, namely, that the oval 
bacillus was a phase in the rapid growth by division of the strep- 
tococcus. Two years later, Heinemann/ after a careful comparison of 
strains of Bacillus acidi lactici from various sources with streptococci 
(sewage, pathogenic, water), concludef that they show no constant 
differences in growth, action on milk, or pathogenicity. Heinemann’s 
work has done much to change existing ideas as to the significance of 
streptococci in milk, for he has shown that the most common organ- 
ism of lactic acid fermentation, existing in practically all milk from 
healthy cows, is a streptococcus (S. lacticus, Kruse). Here again, 
as in the case of leucocytes in milk, it does not necessarily follow 
that streptococci when present are associated with disease. It does 
not seem strange that an organism so widely distributed in nature, 
«Archiv. f. Hyg., Bd. XXV, S. 164, 1895. 
& Ann. Report Storrs Agric. Exp. Station, 1806. 
c Central!), f. Bakt. 1896, Abt. II, Bd. 2, S. 799. 
d Ztschr. f. Hyg., 1899, Bd. 31, S. 337. 
e Arch. f. Hyg.. 1900, Bd. 38, S. 294. 
/Hyg. Rundschau, 1901. 
0jour. app. Microsc., 1902, Yol. 5, pp. 20-29. 
^Ann. Report Storrs Agric. Exp. Station, 1902-3, p. 63. 
i Inaug. Dissert., Bonn, 1904. 
iCentralbl. f. Bakt., 1904, Abt. II, Bd. XI, S. 600. 
k Centralbl. f. Bakt. Abt. I, Bd. 34, S. 737. 
l Journ. of Infect. Diseases, 1906, Yol. 3, No. 2. 
