Other processes of fecundation, to which we shall soon recur, had since 1876 produced the impression in the minds of a number of naturalists that the germ-material led an independent life in the bodies of organisms, that it possessed only an internal development, and required from the body nothing but nourishment in order to multiply itself, and to develop its internal powers uninfluenced by the various vicissitudes of the body. In the year 1876 Gustav Jaeger in Germany, and Francis Galton, a cousin of Darwin, almost at the same time in England, called attention to the observation made some time previously, that in certain animals, particularly in insects, the development of the egg into the young offspring begins with the withdrawal of a small portion of the germ from the component substance of the embryo, which remains at first unchanged and only later multiplies. This observation was generalised and accepted. At the commencement of every sexual multiplication the germ-substance, after impregnation, is divided into two parts, according to its future purpose; an ontogenetic or personal part, out of which the body is built up, and a phylogenetic or germinal part, which at first is stored up unused in the individual, but later furnishes new germ-cells. This idea led Weismann to his view of the continuity of the germ-plasm, which forms an unbroken line of descent from the first beginnings of the species and which is simply nourished by the organisms in which it has its temporary abode. From this germ-plasm spring _secondarily_ the cells that go to make up the body (soma); but from these soma-cells no new _germ_-cells can originate, and consequently none of its inherent or adscititious qualities are capable of transmission. The somatic cells make up the mortal and perishable forms of life, while the germ-cells alone insure the further existence and immortality of the race.