dane 9, 1949.
Dear Max:

I an sending 206, which 4s an °F-2" heterosygote inbred: L.e.,
it is derived by crossing two segreganta from the original H-1. This
stock was prepared to tast the "translceation theory® which I outl ined
at Cinclnnati. In order to facilitate the analysis, a ¥al- mtation
was Lvlucod ii one of the segrezants (Seet¥rx W478) used as 2 parent,
30 that W206 1s haterozygoug both for Lac, and for Mal. However, the
Nel mutation ts cefinitely not the save ae the one In the previous
crosses, ‘hich hag always come out hemi-zygous. The segresstion data
for Lac and Mal are quite abnormal for W-206, so the translocation
theory is not substantlated. However, 1t may be an interesting culture
for single cell work because it fe an F2, and besause the serregatdon
ratios for Lac and Malf/. area as close to eqal. an I have yet seen. The
abnormality is in the co-segregotions: Tho relative freoyencies, in
%, of the poasible combinations of Lec and Mal are:

Lac- Lacs More than in any other stoek, I
think there is a chance here of
Male 31 0 picking up correlated sagregatioas,
Malf _38 31 or at leaet, different kinds of
eogregants.

Unfortunately, ay stock of H-168 has comletely dissociated, and I
have been unable to recover the heteroaygote. Peculiarly, 6-111, which is
presuaably a single cell isclate from it, is pure Xyl~, although secregating
for Lao, Mtl, eta., and I wonder if a “partial” segregation aay not have
occurred. It is also conceivable that H-168 originally was a aixture of
two heteronygotes, one Xyly, the pther Xyl-, and to check these pointe I
am very anxious to try to recover as early a stock as possible. That was the
eocasion for the airmail post card.

The story is at least as enigmatic as ever,

Sincerely,