1. The mottling factor was given the symbol Mt in the Cornell Memoir 180. We have tested several stocks for mottling and have found all except one, C626 purple flint, to produce mottling in seeds of the constitution r r R. However C626 suppresses mottling when the pollen is applied to any r r stock. Hence, it seems to us that mottling is the recessive condition and no-mottling dominant. In 1940 evidence that the mottling factor mt and r are allelic, was obtained. The inbred C78 A C r pr mt (mottling) had been crossed by C626 A C R Pr Mt (mottling). The F1 hybrid was selfed and also pollen was applied to a r mt stock. One ear backcrossed gave 120 colored (none mottled) and 133 colorless. Three selfed ears gave 825 colored (no mottled kernels) to 268 colorless. Although these data are fragmentary they indicate that R and Mt are allelic or very closely linked, much closer than the 12% of crossing over originally calculated by Kempton. Further evidence will be obtained in 1941. I should be glad to receive additional stocks of A C R that are known not to produce mottling.