1. Midcob color. This character is difficult to study in this climate. Samples of the same inbred material were grown in 1941 and in 1942. In several cases a line that had red midcobs in 1941 was classified as having colorless ones in 1942. The ears in both cases were brought in at maturity and dried in the drier for final classification. 1942 was an unusually wet year, especially during August and September. Even under conditions where the ears matured and dried well in the field as in 1943, many ears classified in the field as having colorless midcobs were found to be colored after drying. Proper conditions for complete maturity and drying appear to be essential.
In 1943, apparent linkage was found between an interchange T5-6 and midcob color (30% recombination in 172 plants), indicating at least one midcob color factor may be in chromosome #5 or #6. A new factor for shrunken endosperm (sh2), one of Stadler's x-ray mutants is linked with pr. Backcross data: 150 Pr Sh + 45 Pr sh + 51 pr Sh + 164 pr sh indicate 23.4% recombination. Its location in the chromosome has not been determined.