2. Pales from other compounds involving A^b.

Fifteen pale mutants were obtained from A^b/A plants. These are similar in level of color to A^d and further tests are required to determine whether they are similar in other respects. The plants which gave these mutants were heterzygous for et. Twelve of the fifteen pales carried the et gene which was linked with A in the egg parents suggesting that the occurrence of pales in this compound is related to crossing over.

A similar result has been obtained with compounds of the type A^b/a^b. Here too the large majority of pales carry the et alleles which was linked with a^b in the parents. There is the suagestion, however, that these pales are of different levels. The occurrence of pales of different levels from this compound and not from others that have been tested may well be related to the peculiar action of a^b which has a strong competitive effect. If the varied nature of these pales is confirmed their origin may, for hypothetical purposes, be viewed as a consequence of different local synaptic patterns be viewed as a consequence of different local synaptic patterns at the A "locus" in these compounds and further may require that a^b itself has components separable by crossing over.

John R. Laughnan