The extent of lymphomyeloid repopulation derived from an original FL transplant at the times shown in the PB of primary (1°; left panels) and secondary (2°; right panels) recipients of FL cells obtained from embryos produced from the mating of two W⁴²/+ parental mice. Each 1° recipient was injected with 20% of the cells from an individual FL, and each 2° recipient was injected with one femur equivalent of cells pooled from the BMs of the corresponding group of 1° recipients. The following symbols are used to identify the assumed genotypes of the original FL: ▪, W⁴²/W⁴² ; □, W⁴²/+; and •, +/+.