eo. rest ya Es

THE WEIZMANN INSTITUTE OF SCIENCE

REHOVOTH «ISRAEL K
P.O.B. 26 »'PHONE: 259, 301 1

19th December, 1955

Prof, Joshua Lederberg
Department of Genetics
University of Wisconsin
MADISON 6, Wisconsin

Dear Dr. Lederberg,

I thank you very much for the serine
requiring culture W - 1977 which you have sent us. We have
checked it, and found it to be sensible to very small amounts
of serine, thus enabling us to use it in our serine determinations.

Sincerely yours,

(ere h a rid

Sarah Sarid