. Genetics in relation to agriculture. Livestock; Heredity; Variation (Biology); Plant breeding. 216 GENETICS IN RELATION TO AGRICULTURE evidence has not admitted of an entirely satisfactory interpretation. We shall consider one case, that which Goldschmidt has investigated in Lymantria as an example of the results obtained by investigations of this kind. Goldschmidt's investigations are concerned with Lymantria dispar, the European gypsy moth, and L. japonica, its Japanese form. As may be seen from Fig. 97, Lymantria is strongly sexually dimorphic, the females are much lighter in color and la
. Genetics in relation to agriculture. Livestock; Heredity; Variation (Biology); Plant breeding. 216 GENETICS IN RELATION TO AGRICULTURE evidence has not admitted of an entirely satisfactory interpretation. We shall consider one case, that which Goldschmidt has investigated in Lymantria as an example of the results obtained by investigations of this kind. Goldschmidt's investigations are concerned with Lymantria dispar, the European gypsy moth, and L. japonica, its Japanese form. As may be seen from Fig. 97, Lymantria is strongly sexually dimorphic, the females are much lighter in color and larger than the males; japor^^ca is somewhat larger than dispar, but otherwise in general agrees with it. Goldschmidt's investigations deal with the production of intersexual forms in crosses. -/ ' .-* ' * ^y. O---^ Fig. 97.—Typical forms and hybrids of Lymavtria; 1 and 2, male and female of L. dispar; 3 and 4, male and female of L. japonica; 5-16, hybrids combining male and female characters. (After Goldschmidt.) between these two species. He has shown that with proper combinations of different races of these two species, intersexes may be produced which occupy all possible intermediate positions in a continuous series in which maleness and femaleness are the two extremes. Thus female intersexes, , individuals which are of the chromosome constitution WZ, may be obtained which range from those that show only a very slight develop- ment of male characters in the feathering of the antennae to those which are so nearly males that they show only a faint trace of their female origin in a few minor characters. On the other hand, male intersexes of the chromosome constitution ZZ may be produced ranging from those which exhibit a few white flecks on the wings up to those which Digitized by Microsoft®. 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
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