Germ-Plasm (sprig form), mature germ-cells and the living material from which they are produced.
Hæmophilia (blood love), an inability of the blood to clot. It thus becomes impossible to stop the flow of blood from a cut, and one who has inherited hæmophilia usually dies sooner or later from hæmorrhage.
Heredity (heirship), is usually considered from the outside, when it may properly be defined as organic resemblance based on descent, or the correlation between relatives. But a better definition, based on the results of genetics, looks at it as a mechanism, not as an external appearance. From this point of view, heredity may be said to be "the persistence of certain cell-constituents (in the germ-cells) through an unending number of cell-divisions."
Heterozygote (different yolk), a zygotic individual which contains both members of an allelomorphic pair.
Homozygote (same yolk), an individual which contains only one member of an allelomorphic pair, but contains that in duplicate, having received it from both parents. A homozygous individual, having been formed by the union of like gametes, in turn regularly produces gametes of only one kind with respect to any given factor, thus giving rise to offspring which are, in this regard, like the parents; in other words, homozygotes regularly "breed true." An individual may be a homozygote with respect to one factor and a heterozygote with respect to another.
Hormones (chain), the secretions of various internal glands, which are carried in the blood and have an important specific influence on the growth and functioning of various parts of the body. Their exact nature is not yet understood.
Inborn usually means germinal, as applied to a trait, and it is so used in this book. Strictly speaking, however, any trait which appears in a child at