Apart from those distinctions (preformationism-epigenesis and genetic-epigenetic), the terms "preformistic development", "epigenetic development" and "somatic embryogenesis" are also used in another context, in relation to the differentiation of a distinct germ cell line. In preformistic development, the germ line is present since early development. In epigenetic development, the germ line is present, but it appears late. In somatic embryogenesis, a distinct germ line is lacking. Some authors call Weismannist development (either preformistic or epigenetic) that in which there is a distinct germ line.