Dr. S. FE. Luria,
Dept. Bacteriology,
Indiana University,
Bloomington, Indiana.
Dear Lu-

Although I am not ccavinced of the need for it, I bow to your editorial
prerogatives and enclose an expanded revision of the paragraph relating to
recombination. I have not incluced an apology for the lack of method informa
tion, xhich is adequesely given in the papers that would be read by anypne
who wanted tc use the technijues. If anything, you might include an apologia
for including a nearly irrelevant subject.

I had not included Davis' JACS reference because of his expanded account
in tem (5), and because of ita close contiguity to (22). If you think it
would be better to have it in, please do so:

4b. Davis, B. D.: J. Am. Chem. Soe. 70: 4267, 1948.

Check: your suggested addendum for pp. 7, 10. However, the Tween @0 need
not be more than 0.1%. Title OK.

Tf you are going to be revising the bibliography, I would appreciate it
if you would make the foliowing alterations: Strike out #18, and insert,
after 14,:

l4a. Lederberg, E.Z.: Genetics 33: 617, 1948. In the text, (18) should be
= new 15 atruck out on pp. ll, 15, and (7) substituted for it on p. 15. (lka.)
should be inserted with (11) at the botton of p. 12. This may also mean
substituting (16, 17, 18) for (15, 16, 17)
Sincerely,