. The physical basis of heredity . Heredity. SEX-CHBOMOSOMBS AND INHERITANCE 193 autosomes a factor for pale, and if a spermatozoon, carry- ing the factor for pale, fertilizes each nucleus, the two zygotic nuclei will be ZW female and banded, and ZZ male and pale. This gives at least a formal explanation of the results, and helps us to see how such a rare event, the appearance of two gynandromorphs in the same brood, happened to occur at the same time; because, as Doncas- ter's evidence shows, a double condition may be characteristic of the eggs of certain Fio. 00.—Diagram i
. The physical basis of heredity . Heredity. SEX-CHBOMOSOMBS AND INHERITANCE 193 autosomes a factor for pale, and if a spermatozoon, carry- ing the factor for pale, fertilizes each nucleus, the two zygotic nuclei will be ZW female and banded, and ZZ male and pale. This gives at least a formal explanation of the results, and helps us to see how such a rare event, the appearance of two gynandromorphs in the same brood, happened to occur at the same time; because, as Doncas- ter's evidence shows, a double condition may be characteristic of the eggs of certain Fio. 00.—Diagram illustrating how a heterozygous egg with two nuclei fertilized by two sperms might produoe a gynandromorph like that shown in Fig. SO. "Inteesexes" and Sex G-enbs The quantitative relation of one X for male and two X's for female that has been found to hold in many of the groups of animals might seem from a purely a priori point of view capable of being modified in such a way that an intermediate condition might be realized, but whether such conditions should be expected to give rise to her- maphrodites or to non-sex-somethings (intermediates)— or to a mosaic of both sexes, or should rather be expected to die could scarcely be foretold. There are three cases in which individuals called ' * intersexes'' have been found, or produced; and since their interpretation has led to a view that has appeared to contradict the ordinary sex- determination scheme, these cases must be briefly referred to here. Gold«chmidt has studied very thoroughly '' inter- 13. 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. Philadelphia : Lippincott
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