UNIVERSITY OF CALIFORNIA

DEPARTMENT OF CHEMISTRY
BERKELEY 4, CALIFORNIA

October 2, 1959

Professor Joshua Lederberg
Department: of Genetics
Stanford Medical School
Palo Alto, California

Dear Josh:

Here are some copies of the stuff that Harold Weaver collected
which we thought you would like to distribute to the members of
WESTEX.

I am looking forward to seeing the minutes of our last meeting,
especially since we were not there at its final summation.

Also, I am wondering if you have an opinion regarding the num-
ber of organisms per gram of rock that one might find, say on

a high mountain, or per gram of dry sand from a similar loca-

tion. Also, do you have some idea of the bacterial population
of various kinds of soils?

Tee and very truly yours,

ft

LZ Melvin Calvin
Professor of Chemistry

MC smt
Enes.