Dear Dr. Lederberg,
I was a former student of Prof. C.C. Jan and have just come from China to further my studies on genetics in the Zoological Department of Columbia University. At present I am working with Prof. Ryan on Neurospora.
In reading Dr. Beadle's paper of 1944 on the heterocaryosis in Neurospora crossa I am much intersted [sic] in the quantitative relationship between nucleus ratio and phenotypes. We choose the easily measurable character albino vs. wild as the phenotype. In order to ensure heterocaryotlc conditions we would like to mark the albino and wild nuclei with physiological mutants, Pantothenicless and nicotinicless-2 respectively and let the heterocaryon grow first on minimal media.
We will be very much obliged if you can kindly send us the following cultures of Neurospora crossa: nicotincless[sic]-2-ta-A (4540taA) and Pantothenicless albino-A (5531-15300A).
sincerely yours
T.C. Sheng.