Pebructry 24, 1972

dear Beets,

  `Lfter receiving your letter of Pebruciry 17 I realized that
you should have more information on the chro *oso:::e knob studies of
&to and Blumcnschein.  This was recognized by mention ir; this
letter of the tttble you h,jd constructed of chro,.oso:i&l knob
positions in teosintes and in maize,based on Ting's report and on
that of Langley and Kate.   To clarify this, I am enclosini; some
mtps, most of which were made by Ktzto for his written report, Find
also R table from this report th:tt shows knob distributions ,ind
sizes :-lmong the teosia,tes of Mexico.

  There is a set of m:ips that show the exact eeograiihic loc::tii>ns
from which the ex~~mincd m,aize originated.  You will note that the
coverage is extensive.  -Aso enclosed is a set of di:i:~;r:lrns of knob
positions :tnd. sizes in various basic knob complexes.
L"igure 1 is :1 di                             Kate':: Text
          igr,zrn showing knob r)ositiolLs  that he h:t.:; ob:;ervcd in
eclch of the ten msize chro:ioso @es,   I halve :tcitied a teosinte :,alob at
position 2 in the lorlc arm of chro~rloso .e 1,   K:i to ' :: 'i'ext Figures 4,
6, 8, 9, 10, 12, 14, and 16 illustmte knob :;ositions and sizes that
chtracterize the various basic complexes --those e,trly combi~r:itions
that have contributed so much to pre:;ent day mnize through subr;ecluent
hybridizations, mit;rations, and introductions.   In addition, 1 h*lve
enclosed several maps showing distributions either of p.\rticL;Irzr
knobs or of pirticul`::r chror:-,oso#.,es.
in the long :wm of chro;,?of;o;:le LO.   In two rn:lps, the icnobs we those
                    Both knobs sire z1.1:~ 'y" SRl2ll.

The m:lps of chro;:iouoriles include Abnormal-10 and the B-ty:;e chromo:3o13e.
In ;iddition, there is a rough map th-it I made to show restricted
distributions of "teosinte knobs.'1   pi cluoter of these kno'bs
ch:wxcterize the xnaize race known as Lapnlote Chico (see (ii`-trl;r':tm of
the irlp:Alote Chico knob cOm~JleX, r'igilre 6,
and the:;e sre indic,ited on the map.     p,ity;;e 17 of the iLit re:.;j r-t),
                         The distribution of e ich of the
"teosir,te"' knobs CXL be noted by symbol.  ,:i.thin the 3~::~~-:ric*t~, the
di:;trib;r.ti:)T:s of these knobs :ire restricted.  The follow the
mp:3lote chic0 and i'epitilla  routes north 'a(:  s .outh.
                 f      !e h,:Tvre been
.tble to uncover routes of mier:ition of the v,irious coLlp:~exes pinti :L~SO
into :.dh it geoi;r:i;jhic are:ts a p~;rticull::r comaslex h:::, b<~en intro~~~~ced.
,ie h.LyJe rs:tie m`~ps illustr;;tix,': the indit'idu;tl rolites, intr0.,iluctions,
(nd :~ub~o.~u~nt hybridie;i Aions t&it ha-ze oi;curred in the past.   The se
cover Garth ~Lrawic~, $0 th Amcric.a,  .:ni: the Caribbc:ln Isl:%ntis.
  Now, 1 wish to sh0i.l why I cho:;e to inclutle the two ma~,s il1uutr~;ti.n~
the di!Jtribution of knobs in the lank; corm of chrof.l::;or,e 10.  ,?his
rel:~tcs to the di:~;:,r!tils on ;;'i&;e 13 of the H.K.J-
m,lize.                            `iin report on jikkim
    (Bill i'rown sent me n copy of thin report.)
are supijo:;ed t:., illustrrite the                 Yhe <ii,i,;.r.:rns
                     chyci :oso::ies :lncJ their k:i:;bs in the t;do
exotic rices,  22 1 and L;l? 2.   iieitht:r iii "i;r :m is :ic.cur.ite nncj the


-2.

other chromosome analyses mrike one tremble--horrendous!   Nevertheless,
it is possible to recognize that these two races hyive many of the
teosinte knobs in them.   In this regard,  the two knobs in the long
arm of chror,;osone 10 are highly diagnostic.
Chalco teosinte, in Lapalote Chico,        In the iinericCa.c, 0rAy in
                              :Lnd in two n:iize collections in the
highlands of Guatetia his the presence of both knobs been recognized.
I: suspect that the "primitive" appellcition given to these rices rel:rtes
to the amount of teosinte in them.   They could truly be -primitive or
they could reflect a later occurring hybridization 'between maize and
teosinte whose ch:lrticters had been "fixed" su'bac~uently--like Ar.gentine
Pop.   'i'he maps wo,(ld suggest that these two "primitive" rices could
h ve been imported from the highlands either of Iiexico or of Guatemala.
On this, your guess ia as good HS nine!

   I 4fill comment on other psirts of your letter later.  Just now,
I woiild like to get the enclosed mite-rial to you tiithout delay.