Theory of Germplasm
(i) 'August Weismann' (1889) suggested the theory of continuity of germplasm.
(ii) He referred to the reproductive cells as germplasm and to rest of the body as somatoplasm.
(iii) The germplasm forms the bridge of life and passes from one generation to the next.
(iv) In each generation it also produces the somatoplasm. Soma is 'Mortal' because it eventually dies and disintegrates, the germ is "immortal", because is continues forever.
(v) According to Weisman the germ cells have genetic units ids or determinates.
(vi) He rejected the theory of pangenesis. Thus first time a proper distinction was made between heritable and environmental variation on the basis of this principle.