Abstract
From crosses between red (RRbb) and white (rrBB), F1 and F2 Narrow trisomics (7II + 1INa) gave progeny ratios from selfing which indicate that the extra chromosome of Na carried the Bb but not the Rr locus, and that the 3 members of the Na trisome segregated at random. Normal (7II)F1 sibs gave disomic ratios for both genes.