February 14, 1952

Dear Westergaard:

Greetings: I just happened to receive proof on the C.S.H. symposium,
and was thus reminded of your discussion. I enclose a progress-report just
written which summarizes some of our very recent work precisely on the
subject of sexual compatibility. The whole thing is rather remarkable, but

the experiments are very clear cut. Cavalli and I are colleborating on it
at long range.

With best regards from Esther and myself,

Sincerely,

Joshua Lederberg