_Matzoon._—Matzoon is prepared in Armenia in somewhat the same manner as keffir is prepared in the Caucasus, and indeed it differs very slightly from keffir in composition. Its use is universal in Armenia. _Dadhi._—In India large quantities of fermented milk are used, under the name of Dadhi, and its characteristics are not unlike the similar products in Europe. The specific bacillus has been investigated by Chatterjee,[33] who concludes that it is somewhat akin to the _Bacillus bulgaricus_ and the bacillus of leben (_B. lebenis_). Dr. Chatterjee gives a résumé of his investigations which sums up the whole matter thus: "1. The fermented milk of India called Dadhi resembles in all essential points the Bulgarian fermented milk as well as the leben and other forms of fermented milk in use in the East. "2. The causative element of the curdling process of Dadhi is a streptothrix having characters similar to the _Bacillus bulgaricus_ and _Streptobacilli lebeni_, and _Bacillus caucasina_ and the Long Bacilli of Mazun, in (1) not growing in ordinary media; (2) producing a large amount of lactic acid in milk; (3) producing, besides coagulation of casein and splitting up the sugar of milk into lactic acid, no other change in milk; (4) not producing any indol, nor peptone, nor saponification of fat, nor formation of any gas. "3. It differs from the above by showing peculiar pink-stained granules, when stained with methylene blue and showing peculiarly convoluted chains in glucose agar. "4. The importance of the organism lies in the fact that, as in the case of _Bacillus bulgaricus_, it kills all pathogenic non-sporing germs and also destroys all proteolytic gas-forming bacilli in milk." In the account of these investigations the following table is given, showing the amount of lactic acid produced by different lactic acid bacilli in one litre of milk, in terms of lactic acid—the culture being kept at 37° C.