. Sex-linked inheritance in Drosophila. Heredity; Drosophila. NEW DATA. ss The data give 43 per cent of crossing-over, which places fused far to the right or to the left of eosin. The latter position is improbable, since eosin already lies very near the extreme left end of the known series. Therefore, since 43 per cent would place the factor nearly at the right end of the series, the next step was to test its relation to a factor Hke bar that lies at the right end of the chromosome. By mating to bar alone we could only get the linkage to bar without discovering on. Fig. D.—o, normal wing; 6 an
. Sex-linked inheritance in Drosophila. Heredity; Drosophila. NEW DATA. ss The data give 43 per cent of crossing-over, which places fused far to the right or to the left of eosin. The latter position is improbable, since eosin already lies very near the extreme left end of the known series. Therefore, since 43 per cent would place the factor nearly at the right end of the series, the next step was to test its relation to a factor Hke bar that lies at the right end of the chromosome. By mating to bar alone we could only get the linkage to bar without discovering on. Fig. D.—o, normal wing; 6 and c, fused wings, c shows a typicalfused wing. The most striking feature is the closure of the cell between the third and fourth longitudinal veins with the elimination of the cross-vein; the veins at the base of the wing differ from those in the normal shown in o. b shows the normal position in which the fused wings are held. The fusion of the veins in b is unusually complete. which side of bar the new factor lies, but by mating to a fly that carries still another sex-linked factor, known to lie to the left of bar, the infor- mation gained should show the relative order of the factors involved. Furthermore, since, by making a back-cross, both males and females give the same kind of data (and need not be separated), the experiment was made in this way. In order to have material for such an experi- ment double mutant stocks of vermilion fused and also of bar fused were made Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Morgan, Thomas Hunt, 1866-1945; Bridges, Calvin B. (Calvin Blackman), 1889-1938. Washington, Carnegie Institution of Washington
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectheredit, bookyear1916
