This is in answer to your letter of the 8th of August. I did not receive your previous letter although usually such mail
is forwarded. It probably came at a time in St. Louis when the secretary was on vacation and I shall undoubtedly get it subsequently.
I am sending to you under separate cover the Proceeding's paper as well as several others which you may find of interest.
Unfortunately I did not receive reprints of the review in the Sumner and Myrback Book. The publishers do not send reprints
until the book has been in print for about a year, presumably to stimulate purchases. When and if those reprints arrive,
I shall certainly send you a copy.
I am also sending to you, under separate cover, by ordinary mail a manuscript of a paper which will appear in the proceedings
of the National Academy of Science and which I think you will find of some interest. It deals with a single cell analysis
of the reversion from the positive to the negative phenotype, and the results confirm rather completely our interpretation
of the long term adaptation phenomenon. In addition the data are of a nature which permits one to estimate the number of
particles in an adapted cell, the minimum number required for a cell to be positive, and the probability of any particle passing
from the mother into the daughter cell. I shall greatly appreciate your reaction to this paper.
Our work here has proceeded amazingly well within the last year and a half and much of our recent success has stemmed from
the analysis of stocks exhibiting the "long term" phenomenon. We have recently succeeded in completely verifying
the original melibiose experiments with the galactose system by demonstrating that the presence of galactose during the segregation
yields 4 spores of the positive phenotype. Putting these through a reversion experiment invariably yields 2 plus and 2 minus
cultures. The same material is also enabling us to answer some rather subtle questions which we could not have hoped to have
tackled experimentally with the aid of normally adapting stocks.