Gene affecting egg color. Maternale inheritance.Spontaneous;serosa cells pigmented light brown, maternal inheritance in F1 egg color but ordinary inheritance in F2;transmission of 3-hydroxykynurenine from hemolymph to the ovum is somehow prevented, and enzyme action in serosa cells is too weak to convert it into pigments: Typical maternal inheritance in egg color of b-2na (maternal brown of Nagashima) .