THE UNIVERSITY OF WISCONSIN
COLLEGE OF AGRICULTURE

Madison, 6

DEPARTMENT OF GENETICS

May 21, 1952

Dear Luca:

I apologize for having delayed so long. This package has the following
E, colis

58, 679, W-1305, W-1678 per previous description
W-1258A (= a"prototroph"from your NTCC 123)

W-1930 and W-1937 are diauxotrophs from the above.

W-1982 is a non-lysogenic 58-161, also sent to Hayes. a J)
ff

In a few slides of HfrX I have seen many cells look like: LS and

occasionally pairs 1: x . 222 2Cregiuga lions
Sincerely, Jrptuo—

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