The dominant white cap (W^c) endosperm factor is linked with brittle stalk (bk₂) in chromosome 9, the backcross numbers being 135 W^c +, 67 W^c bk, 65 w^c +, 143 w^c bk, or 32.2 per cent recombination. With T 8-9a there was 30 per cent recombination (W^c - T 8-9a = 18:33:68:25). Since tests reported previously indicated no linkage with waxy (News Letter 18: 16. 1944) the order appears to be wx - bk₂ - W^c; or wx - T 8-9a - W^c.

A brown midrib character which appeared in a sh wx gl₁₀ culture seems to be genetically different from the other three brown midribs, and therefore is bm₄.

Viviparous (vp₅) is the same as Woodworth's vp as shown by intercrosses. Tests are in progress to determine the linkage group to which vp₅ belongs. This will also locate one of the factors for yellow endosperm (unless vp₅ itself causes the color effect).