May 8, 1954

Dr. Benigna Blondel
159 Elm Street
Northampton. Maas.

Dear Dr. Blondel:

Thank you for your letter of May 6. By coincidence, I had received
only yesterday copied of your reprints from Dr. Welsch. As your personal
supply may be limited, you perhaps prefer to have these back. I read them,
of course, with great interest.

As concerns the comment in your note at p- 1491, Etalement des clones,
it is of course self-evident that colénies may be somewhat smeared by impression
of the velvet, and that the transfers often consist of local clusters of
colony-formers. Similarly, unless, on the average, a fair number of cells
were usually deposited from evan a small clone, then chance would dictate
the frequent failure to deposit any. Like yousself,we had tested a conaiderable
range of fabrics, ami found domestic velveteen (i.e. velours de coton) to
be, on balance the most suitable. Have you, by the way, seen Elek's
remarks (J. Clin. Path. (It. Brit, 7:37, Feb. 1954)? These minor variations
are entirely unimportant, but I find it difficult to understood why he adopted
the cumbersome procedure of moving the velveteen, attached to blocks, rather
than the plates.

To return to the point of your letter, I am sorry to have to report
that the commitments wa have already made leave no possible space, so that I
am unable even to consiler your application. Unfortunately. the same is true
at our Bacteriology department. In New York City, however, there are two
laboratories where you might be more fortunate » and which you provide you with

an equally suitable opportunity for experience. I recommend that you commni-
cate with:

Professor F. J. Ryan Dr. S. E. Hutner
Dept. Zoology and Haskins Laboratory
Columbia University 305 E. 43 Street
New York 27, N.Y. New York 17, N.Y.

Dr. Ryan is well knom for his studies on selection dynamics in bac terial
cultures, while Dr, Hutner's group has made outstanding contributions in

the physiology and genetics of the algae, including specially effects of :
antibtééics. /

Yours sincerely, /

| y\

i 7 ve 7 - Joshua Lederberg a | Q
. -/ DA Associate Professor of Genetics |

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