The dominant white cap (Wc) endosperm factor is linked with brittle stalk (bk2) in chromosome 9, the backcross numbers being 135 Wc +, 67 Wc bk, 65 wc +, 143 wc bk, or 32.2 per cent recombination. With T 8-9a there was 30 per cent recombination (Wc - 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 - Wc; or wx - T 8-9a - Wc.

 

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).