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Dehydrated Infusion Media for the Propagation of the Pathogens

This group of Dehydrated Cutture Media, Difco, is prepared expressly for the cultivation of the fastidious pathogenic bacteria. The "growth fac- tors" of the original tissue infusions are preserved in the dehydrated media.

Bacto-Brain Heart Infusion When made up for use in the laboratory this product yields an excellent liquid medium for the propagation of the streptococci. The addition of a small amount of agar (o.i to o.z per cent) further enhances the growth promoting value of the medium.

Bacto-Blood Agar Base This medium is a "hormone" agar with a slightly acid reaction when it is prepared for use. It is an excellent base medium for preparing blood agar and is recommended for this purpose. The degrees of hemolysis produced by organisms on plates of blood agar prepared from this medium are excep- tionally clear and distinct.

Bacto-Dextrose Heart Agar This medium, when it is prepared for use, corresponds to an infusion agar enriched with dextrose and having a slightly alkaline reaction. When further enriched with blood or other body fluids it is an excellent medium for the isolation and cultivation of many of the fastidious organisms.

Bacto-North Gelatin Agar When this dehydrated medium is made up for laboratory use it corresponds to Dr. Spray's modification of the original North formula, tt was developed especially for the propagation of the gonococcus and is an excellent substrate for this organism as well as for many others.

Specify "'DIFCO" THE TRADE ~ME OF THE PIONEERS In the Research and Development of Bac~o.Peptone and Dehydrated Culture Media DIFCO LABORATORIES INCORPORATED DETROIT, MICHIGAN

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