The present Standard Methods agar for the bacterial plate count of dairy products, so-called T.G.E.M. agar (Tryptone, 0.5 percent; dextrose, 0.1 percent; beef extract, 0.3 percent; skim milk, 1.0 percent; and agar, 1.5 percent), has been in use for more than 10 years.' This medium, called the standard medium in this report, was fonnulated when attempts were made to obtain a more productive agar than the official standard medium existing at the time. It fulfilled this purpose and was adopted. That it is not an ideal medium is attested by a number of persons who use it routinely.The disadvantages stem from the presence of two ingredients.One of the ingredients, skim milk, gives rise to several difficulties.In the first place, it takes skill to add skim milk to the medium successfully in the form of dissolved dried powder. Second, after being added to the medium, milk sometimes exhibits a tendency to settle out when the medium is held in a tempering bath prior to pouring. Finally, and perhaps most important, milk induces cloudiness in the agar which, although seeming to make colonies stand out more distinctly at times, actually tends to make counting more difficult.This difficulty is due to the selection which the eye must make between very fine particles of milk and fine colonies. There is little question that, as a rule, colonies on a clear medium are more easily counted. During the experimental work presented here, technicians experienced in the use of the standard medium volunteered the information that the new milkless media studied caused less eyestrain.A second objection to the present standard medium is the presence of a nonstandardized product, beef extract. The best information

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