'l'he lactic acid producing streptococci show certain differences, some of which must be of importance from the standpoint of the growth of these organisms in dairy products. A classification of this group of organisms has been proposed; it is not presumed to be complete and other types will necessarily be added. The classification is as follows:

Typical S. lactis

Malty S. Iactis—S. lactis var. maltigenes

Ropy S. lactis—S. lactis var. hollandicus

Slow reducing S. lactis—S. lactis var. anoxyphilus

Slow coagulating S. lactis—S. lactis var. tardus

Heat resistant lactic acid streptococci—S. thermophilus