CALIFORNIA INSTITUTE OF TECHNOLOGY
PASADENA

September 5, 1945

Dear Mr Lederberg:

I am sending the reprints you requested under separate cover.
Dr Cushing was working on adaptation of “eurospora to the sulfa
drugs during his spare time while working on a war contract. He has
just finished that and has now left to take a position at Johns
Hopkins (Department of Biology)+ Before he left, I went over his
results with him¢ and there is little to report at this time. If
he does not find time to continue the work shortly, I shall probably
have a stab at it myself. It is quite a problem to distinguish
between mutations induced by the treatment and those normally occurring
but selected for by the treatment.

Very truly yours

Sterling Emerson
Assoc. Prog. of Genetics