But because the Recessive traits of Dwarfness and of Whiteness were only _overpowered_ in the plant-development, by the Dominant traits of Tallness and Colour, but were neither lost nor impaired in stock, hybrid plants that had shown only Dominant traits in growth and constitution, produce, nevertheless, two sorts of sex-cells for plant-reproduction: cells that bear the Recessive traits of the one parent, and cells that bear the Dominant traits of the other parent. So that in the fertilisation of one another by such hybrids, cells bearing Dominant traits mate with other cells bearing Dominant traits, and produce plants of pure Dominant type--Tall or Coloured, like one of the grandparents. While cells bearing Recessive traits mate with other cells bearing Recessive traits, and produce plants of pure Recessive type--Dwarf or White, like the other grandparent. It is seen, therefore, that in plants, when a cell bearing Dominant traits mates with one bearing Recessive traits, the Dominant characteristics so overpower the Recessive that these latter lie latent, and concealed, in the resulting plant. But when a cell bearing Recessive traits mates with another cell bearing Recessive traits, the resulting plant (its growth and development not over-ridden now by the more assertive Dominant traits) is able to develop its Recessive characteristics. * * * * * These interesting and significant laws of plant-heredity and constitution, discovered by Mendel in peas, have since been found by many expert observers to hold true as regards other species of plants; as too in poultry, in mice, and in rabbits, and moreover, in the hereditary transmission of human characteristics. In _Heredity and Variation_, Dr. Saleeby points out that in the mating of a black with a white rabbit, some of the offspring will be black like one parent, some white like the other, and some grey--a blend of the colours of both parents. In the last case, the _Dominant_ trait of Blackness, derived from one rabbit-parent, blends in the fur of the rabbit-offspring with the _Recessive_ trait of Whiteness, derived from the other rabbit-parent; a grey rabbit resulting. But that the Contrasted Traits come to no more than a temporary and partial compromise during the life of such a rabbit-individual, without either of the traits losing its intrinsic characteristic--Blackness and Whiteness, respectively--is proved by the fact that these grey rabbit-offspring, on further breeding, produce not _grey_ rabbits, but black rabbits and white rabbits; proving that the Black trait and the White trait in them remained distinct and segregated, neither altering its character in the least degree.