UNIVERSITY COLLEGELONDON -GOWER STREET WCI

DEPARTMENT OF ZOOLOGY

Professor P. B. MEDAWAR Telephone RUSTON 7050

July 4th 1957

Dear Dr. Lederberg,

For several weeks I have had on my desk the
reprint you so kindly sent me, and I dare not begin
to apologize for not having written the comments on
it which you invited. Even now I am only writing, I
am afraid, to acknowledge its receipt, for I have
yet to digest all its implications. But I can see
that it could be very relevant to the question of
cell 1 neages in ageing, and to the process, which
may occur more often than histologists seem to
admit, whereby cell division results in one senescent
and one non-senescent daughter.

Most of all I would like the opportunity of
talking to you about it. Do you ever attend any
congresses in this country ? If you do, and could
spare me a lunch-time, I very much hope you will
visit me.

Yours. sincerely,

arn

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