GENUS BACTERIUM 303 



Grigoroff l who examined, in Massol 's laboratory, * ' Yoghurt, ' ' 

 the fermented milk of Bulgaria, and named the organism B. 

 bulgaricus or the bacillus of Massol. Emmerling 2 saw a long 

 bacillus in Armenian fermented milk "Mazum" but was un- 

 able to cultivate it. A number of other investigators have 

 found organisms which they have more or less fully described 

 and which appear to be identical with Bact. bulgaricus. Heine- 

 mann and Hefferan 3 have studied the distribution of this or- 

 ganism somewhat carefully and recorded its morphology and 

 cultural characters. They found it in a number of samples 

 of cow, horse, and human feces, saliva, in bran, ensilage and 

 brewers ' grains, in certain foods and spices, such as corn meal, 

 sauerkraut, olive juice, dill pickles, and in the soil from a 

 paddock where horses and cows were kept, and in garden soil. 



Morphology. This bacterium usually is square cut at the 

 ends. It often occurs in short chains and in milk in quite 

 long filaments. Heinemann and Hefferan report true dichot- 

 omy, the organism appearing in the shape of the letter Y. 

 According to these authors it exhibits a great variety of forms 

 both in length and thickness. The morphology of the organ- 

 ism seems to be more characteristic when grown in milk where 

 it appears as long irregularly stained filaments and single 

 shorter rods, both showing unstained portions or vacuoles with 

 often slightly enlarged ends. 



Staining. It stains readily with the ordinary dyes and 

 is Gram positive. It appears to be stained best by Weigert's 

 modification of Gram's stain. 



Cultivation. For the isolation of this organism the 

 method employed by Heinemann and Hefferan is given. "The 

 material to be examined is- added to a tube of litmus milk and 

 incubated at 42 C. for 24 to 48 hours. Feces or other ma- 

 terial containing large numbers of bacteria was added to acid 



'Grigoroff. Revue Med. de la Suisse, Rom. Geneve, Vol. XXV 

 (1905) p. 714. 



2 Emmerling. Centralbl. f. Bakt., Bd. IV (1898) p. 418. 



3 Heinemann and Hefferan. Jour, of Inf. Diseases, Vol. VI (1909) 

 p. 304. 



