April 2, 1962
Dear Dr. Brieger:
I understand that Dr. Almiro Blumenschein will be coming this summer to the 
North Carolina State College at Raleigh.  Dr. Wellhausen has asked Dr. William L. Brown and me to select some maize material that we consider appropriate for chromosome examinations by Dr. Blumenschein and by others who will be at North Carolina.  We would very much like to have included in this some of the races that you have described in your maize monograph.  Dr. Brown has selected some races that he considers would be appropriate for this purpose, a list of which is enclosed on a separate sheet.  It would be most convenient for us if Dr. Blumenschein could bring the seed with him.  For the purposes of determining the origins and migrations of races from studies of their chromosome composition, it is quite necessary that original collections be used as bulked seed of a race would not serve the purpose.  Also, it is most important to know the exact geographic location where the plants were grown from which seed was obtained.  Otherwise, erroneous conclusions could be drawn from the chromosome studies.  It is possible that you may not now have stocks of seed of the desired races that fulfill the stated requirements.  If, however, you do have them, we would appreciate having 100 kernels of each collection, particularly of those that are starred in the list.
Dr. Brown suggests that after the kernels have been dusted with DDT, the packets of kernels be placed in one package.  An import tag would need to accompany the package, I believe, also, that Dr. Brown would be able to obtain a pass for their entry into the United States.  If I hear from you that some collection will be available to us, I will contact Dr. Brown immediately about the pass.
It is possible that you may have heard that the Department of Genetics of the Carnegie Institution is being closed down.  It will cease to exist as a Department at the end of this coming June.  I will stay here at Cold Spring Harbor for a while, at least, until we know whether or not the new Institute that we are trying to form will materialize.  If it does, it will incorporate into one Institute with a completely new sponsorship all the former property of the Department of Genetics of Carnegie Institution and also all of that of the Long Island Biological Association.
With best regards to you and Mrs. Brieger,
Sincerely yours,
Barbara McClintock
LIST OF RACES DESIRED
1.*  Amarillo de Ocho
2.  Oke
3.  Pisincho
4.*  Brachytic popcorns
5.  Calchaqui White Flint
6.  Calchaqui Small White Flint
7.  Calchaqui Small Yellow Flint
8.*  Avati Morotf (Guarani Flour)
9.  Avatf Djakaira (Guarani)
10.  Avati Moroti Guapi (Guarani)
11.  Avati Moroti Mita
12.  Avati Pichinga - Guarani popcorns
13.  Avati Pichinga - Ihu - Guarani popcorns
14.  Chavantes Opaie
15.  Lehna
16.  Caingang Icatu
17.  Caingang Vanuiri
18.*  Southern Cateto (in its various forms)
19.*  Canario de Ocho
20.  Interlocked Soft Corn
21.  Maisirara
22.  Guarare
23.*  Northern Catetos - from the Guianas and Amazon basin