3 o8 



The " Long Lactic Bacteria." [July, 



Bacillus Bulgaricus, a name at present very generally applied 

 to such "long lactic" organisms. Also in Armenian 

 "mazun," Dioggoli discovered a germ of similar characters; 

 and in Sardinian sour milk "gioddu," Grixoni observed a 

 long lactic type of organism. 



All the cultures of long lactic bacteria obtained by different 

 workers from the various fermented milks possess the same 

 general characters, and such bacteria form a distinct group. 

 Lohnis * has classed them in the Bacterium caucasicum 

 group, and has lately f adopted the term " lacto bacilli," 

 formerly used by Beijerinck, and for various reasons this 

 term is preferable to "long lactic bacteria," "S. Bulgaricus 

 type," &c. 



White and Avery J have isolated different varieties or 

 strains of this type. They have made a comparative study 

 of a large number of cultures of lactic acid-producing, milk- 

 curdling bacteria from many countries, all originally isolated 

 from Oriental fermented milks. Their results justify Lohnis's 

 classification, and show that every culture studied must be 

 included in the lactobacilli group. 



The general conclusions arrived at by these investigators 

 as to the characteristics of the bacteria of this group — the 

 so-called Bulgaricus type — may be summarised as follows : 

 All the strains show wide variations in size and are much 

 larger than the ordinary milk-souring bacteria. They may 

 vary in length from 2/x to 50/A and are about i/x broad. The 

 bacteria of this group are difficult to cultivate ; growth in 

 most media is feeble, and often obtainable only in media 

 containing milk or whey, or in milk. Milk is the most 

 favourable medium for growth. The optimum temperature 

 for growth is much higher than in the case of the ordinary 

 lactic organisms, being 113 0 F. or 115 0 F. Milk is coagulated 

 in eight to eighteen hours at 1 12 0 F. Such organisms produce 

 a much higher degree of acidity in milk or whey than the 

 normal milk-souring bacteria. 



Grown in whey agar all the strains show the following 

 cultural characters: They grow equally well under aerobic 



* Gruppierung der Milchsaurebakttrien, Ceniralblatt fur Bakter., Bel. 18, 1907. 

 t Handbuch der Landwirtsch. Baktei'iologie, 1 9 10, 

 X Ceniralblatt fiir Bakier., Bel. 25,-1909. 



