they bring into our ephemeral consciousness an unknown psychic life belonging to a remote past. It is the mind of our unknown ancestors, their way of thinking and feeling, their way of experiencing life and the world
Jung locates the archaic psyche in the phylogenetic substratum of the collective unconscious, identifying it as the ancestral mind that anima and animus carry into present-day consciousness.
, The Archetypes and the Collective Unconscious, 1959thesis