Dirco LABORATORIES iy

DETROIT 1, MICHIGAN

ESTABLISHED 1895 CABLE AppRESS “DIFCO”

PHONE WO. 1-0800

Stanford University June 25, 1960
Dr. Lederberg
Palo Alto, Cal.

Dear Dr, Lederberg:

On several occasions we have had inquiries requesting the formulation
of your modified EMB Agar for genetic studies, The medium has been
referred to as EMS Medium of Lederberg. We have been unable to find
this in the literature and would appreciate your giving us the refer-
ence to your publication describing the medium and its uses and if
possible to send us reprints on such articles,

Thanking you for this service, I am

Yours very Sincerely,

fd C.W. Christensen, Ph.D
Director, Microbiology

' See: Methods in Medical Research 1950
3: 5 table 1C¢

Subsequently also used with omission of succinate
see: encl. ref. ll.