_» BHR JOHN INNES HORTICULTURAL INSTITUTION. -

51, Mostyn Road,
Merton Park,
London, S.W.19,
England. -

llth Maroh, 1947.

Dear Lederberg, . +

- o> I must. apologise for my , delay in replying to your
: - last two letters. I am a bad correspondent, and you will.

of grow: accustomed to such apologies from me.

 

First of all, ‘one or two points from your letter of
eth February. You are, of course, quite right (p.2. parae3) —
that on the earlier evidence V is linked with L &/or P rather
than with L & P. It looks now as if "&" is correct and not ~
"or", but it. was not clear at that time. .

How do you propose to test 2 or 4 strand crossing-over?
I thought it could-be done only where more than ons .strand
can be recovered from the.same meiotic configuration, and I
' Was not aware of any possibility of doing | this. in your -
material. \

You say you think the posaipdlity of’. spurious Linkages

Like BeeeeseoM has been covered. Are.the data final on this -—
, point, as_ it Seems. to. me - of basic importance? , ,

“@he experiment. you. outlined in - your first. letter. end

nose results you\gave in the later. one of March Srdis. ‘very

 

_.. Waluable. It seems to place V between P & L as‘you say; but.
“I am not clear about its implications for the left-end. of the
_map.e, This is probably due to my incomplete appreciation: of

_ the experiment, for I am not clear about one or: two. ‘technical

   

 

points. Did M enter into it? I thought not.at- first, out.
. then you refer to crosaing-over in region F (between‘B & M)
_ dn your discussion of the results from the B. datas; In using
~ B plates to estimate the ratio of B~:and B+, do you insist on >
the bacteria being By4#? And in estimating the By~ :.B; atio
_ do you insist on them being B+? - -Protetrophs,.I x
“Bat + Bt P+ it THs: “- ask about: the oints ‘a

 
as I see no theoretical reason why a two demensional system
should not also have such suppressors. JI feel myself that
tests of the kinds listed as (a) and (b) in my last letter
should be capable of settling the linearity question as
clearly as anything else, if you have the genes for them.

qe

The second edition of my "Statistical Analysis in
Biology” is now available, I'm @lad to say.

I hope that you will find time to continue letting
me know how your experiments are getting along. I find them
intensely interesting, from both the analytical and theoretical
points of view. I have told Darlington about them and he too
is very interested. He suggests that you may care to write
something about them for the new Journal "Heredity" which he and
Fisher have founded, and the first number of which should be
out either this month or next.

Please give my best wishes to Mrs. Lederberg.

Yours sincerely,

Dr. J. Lederberg,

Yale University,

Osborn Botanical Laboratory,
New Haven,

Connecticut,

U.S.A.