7. We apparently have two complementary factor pairs for yellow endosperm. I have tentatively designated one of them Y₄ and the other It (intensifier). I have only one stock of Y₄ Y₄ it it, but It is carried by several white stocks, in fact, all so far tested except one a-tester. It might be an allelomorph of A. F₁ seed of the cross Y₄ Y₄ it it x y₄ y₄ It It is all yellow. The F₂ ears segregate fairly well into a 9:7 ratio for yellow and white, showing several intensities of yellow. I do not think the stock of Y₄ Y₄ it it is the same as Y₁. It is much lighter in color and shows segregation well only in very flinty corneous stocks. The intensifier stocks, y₄ y₄ It It, also intensify the yellow color of Y₁.