Dear Dr. Friedrich-Freksa:

I have read with deepest integgst your paper in Nd tyeW/
Z. Naturf. on the segregation of P7“-induced lethals in Amoeba
proteus. May I request a copy of this publication? Inteed, I
would be grateful to you for a more comprehensive exchange of

papers on topice of mutual interest.

Recently, we have been concerned with a reminescent systen
of" segregation" of /¥d%¢ quasi-genéio units, in the course of
transduction experiments in Salmonella. In addition to the stable
genetio alterations (of a motility character, i.e., “swarms") one
finds what Stocker and I had Pegarded as abortive transductions, or
Femotilized cells that do not regularly transmit this character to
their progeny. The behavior of pedigrees from single motile cells
suggest that a polytenic bundle of factors is initially trandduced, and
later parcelléd out to the progeny. Other interpretations are, however,

possible.
Yours ee
JA oe A ;
bessca Cache!

Professor of Gen cs