April. 20, 1955
Memorandum

Trac y:

i. Kimura ig working on generalizing the formlae. Preliminary report on
macronudlear sampling (MR)- for f fragments, each instance is 2&#¢ 2(f-1)
as effective as fission. That is, for f£=40, 6 MR's would be equivalent to
368 fissions. The discrepancy, if any, may be due to non-random choice of
less unbalanced fragments. I was momentarily concerned by the case of
f£=2, which I took to be fission, Kimura points out his caleulation for
fission 1s based on a redoubling of chromosomes from mn to 2mn prior to
fission, while the MR is tdomm taken from an mn set. If this is not right,
you can probably just take out the factor 2,

2. He is also going ahedd on moncscmic. If n ia large, the effect is small
(probably some kind of weighted mean [my intuition sees geometric] of the
riska from the monosome and tha rest of the complenent), of the order of

a reduction of viability by about 1/2n,I am somewhat dubious of this.

3. As you can see from expression you have, p= .01 and n=.001 do not give
very different t's. On the one hand, this fits the steep decldne seen exptly,
but the p/t function would not be handy to test.

4. Referancas: bud scars in yeast—- Barton, J. Gen. Mier. 1950,4:84 and
Bartholomaw, 1953 J Bact 65:272

agifing in Neurospora mitant TT Sheng, Genetics 51 36:19°
stem cells in spermatogenesis Clermont Am J Anat 92:475 '53

see also Roosen—-Runge in refs. cit., and ina regent N.Y. Acad
Sed, symposium on male germ cells.

5+ Refs. wanted? = pisston reorganization 4n protozoa; other cases of
templates like Difflugia.

6. In his 1929 review, Jennings cites a few examples of protozoan "individual ity"—
shattering reaction on refusion of distinct individuals. Do you be:ieve this?

Sincerely,

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