March 13, 1969

Dr. K. Yamakawa

Institute of Radiation Breeding
Ohmya, Ibarbki

Japan

Dear Dr. Yamakawa: cc

Dr. A. H. Sparrow at Brookhaven suggested that I write to you for
information on microbiological studies that may have been made on

the soil near outdoor gamma sources. I am interested in the possi-
bility of natural selection for highly radiation-resistant bacteria,
and have already found some interesting organisms from the Brookhaven
site, different from Micrococcus radiodurans.

If you know of any publications or have other information on this
question, I would ge grateful to you for the sourtesy.

Sincerely yours,

Joshua Lederberg
Professor of Genetics

VOY Y VY