1. Darlington, C. D., “Chromosome Botany” (London, 1956).
2. Buchholz, J. T., and Gray, Netta E., J. Arnold Arb., 29, 49 (1948).
3. Stiff, McHenry, L., Ph.D. Thesis, University of Virginia (1952).
4. Mehra, P. N., and Khoshoo, T. N., J. Genet., 54, 181 (1956).