Shows extremely reduced recovery from above heterozygous females (Lindsley and Novitski, 1959), all zygotes carrying YSXYL. being lethal in some autosomal backgrounds; reciprocal recombinant recovered frequently (Novitski and Brosseau, 1964; Donady et al., 1973).
Lindsley.
YSXYL., KS y1 KL..