+---------------------------+---------+---------+------------+ | Gens. | Total. | Cross- | Cross-over | | | | overs. | values. | |---------------------------+---------+---------|------------| | | | | | |White reduplicated | 418 | 121 | 29.0 | |Reduplicated vermilion | 667 | 11 | 1.7 | |Reduplicated bar | 583 | 120 | 20.6 | | | | | | +---------------------------+---------+---------+------------+ The most accurate data, those upon the value for reduplicated and vermilion, give for reduplicated a distance of 1.7 from vermilion, either to the right or to the left. The distance from white is 29, which would place the locus for reduplication to the left of vermilion, which is at 33. The data for bar give a distance of 21, but since bar is itself 24 units from vermilion, this distance of 21 would seem to place the locus to the right of vermilion. The evidence is slightly in favor of this position to the right of vermilion at 34.7, where reduplicated may be located provisionally. In any case the locus is so near to that of vermilion that final decision must come from data involving double crossing-over, _i. e._, from a three-locus experiment. LETHAL 1. In February 1912 Miss E. Rawls found that certain females from a wild stock were giving only about half as many sons as daughters. Tests continuing through five generations showed that the sons that appeared were entirely normal, but that half of the daughters gave again 2 : 1 sex-ratios, while the other half gave normal 1 : 1 sex-ratios. {32}