STANFORD UNIVERSITY
STANFORD, CALIFORNIA

DEPARTMENT OF
BACTERIOLOGY AND EXPERIMENTAL PATHOLOGY

October 1, 1951

Dr. Joseph Lederberg
Dept. of Genetics
University of Wisconsin
Madison 6, Wisconsin

Dear Dr. Lederberg:

we are sending you a culture of our stock K-12
which we keep simply by transfer at appropriate in-
tervals. We do not have any lyophilized cultures
and I know of no laboratory that may have one. Our
strain appears to give a rather large number of
smooth colonies on plating.

We have 25 or more strains of E. coli which we
have had in the laboratory for many years, most of
them dating back about 20 years when studies on phage
therapy were in progress. I can send you cultures
of these if you so desire.

Sincerely yours,

LE Lao

C. E. Clifton

CEC/ss