April 23, 195)

Dr. Louis Dienes
Massachusetts General Hosp.
Boston 1)

Massachusetts

Dear Dr. Dienes:

Thank you for your letter of April 21,

I am sorry that I do not have any cultures or phages of 3B. megaterium
and cannot therefore meet your request. Perhaps Dr. Philip Cowles at Yale
University would be able to help you, or alternatively Dr. Max Delbruck at
the California Institute of Technology, who is in close touch with Dr. Lwoff,

You alse mentioned your interest in lysogenic typhoid, I have not my-
self worked extensively with this Salmonella species, As you know, almost
every culture of Salmonella typhimurium is lysogenic, I believe I did send

you some cultures of the material we had been working with some time ago, but
if you have /specific requirements that we can fulfill, I will be glad to send

them. °
T am sorry that I will not be attending the meetings at Pittsburgh,
«ith best regards,

Yours sincerely,

Joshua Lederberg
JLamg
P.S. I trust you will have noted the abstract in the Sacteriological Pro}
ceedings by Hutchinson, on the failure to fini any genetic evidence of sexual
behavior of large bodies, In view of your previous exveriments with Proteus,
T suppose this is no surprise,

dele