Multiple Allelomorphs in Colour Vision

EVIDENCE has been found that the main forms of defective red-green colour vision in man are multiple allelomorphs, alternative to each other and to the normal form1. In order to prove this hypothesis it would be necessary to show : (a) that the forms of red-green vision are discontinuous variations ; (b) that they are inherited true to type ; (c) that they segregate independently ; and (d) possibly that they have an order of dominance. It will be seen that the evidence in favour of the hypothesis is very strong.