Aquaster, actually. Jung apparently noodled with the Paracelsan idea of the aquaster.
The PDF abstract of Jung's collected works found at the link below has this:
The Iliaster and the Aquaster are compared, and the latter is described as a spiritual principle whose characteristics correspond to the alchemical concept of the water in prima materia. Christ is said to have taken his body from the celestial Aquaster; Mary, from the iliastric Aquaster. The Aquaster is interpreted as a psychic principle, closely related to the modern concept of the unconscious. In Paracelsus' writings, it was personified as the homunculus. Both Iliaster and Aquaster were believed to extend upwards and downwards, assuming a spiritual form as well as a quasi material one; in this respect they are seen to resemble the alchemical prima materia.
And this:
The alchemical concept Ares is discussed and compared to the Paracelsan Aquaster. In the alchemic view, Ares is presented as the determiner of individual form and species, hence, an intuitive concept for a preconscious, creative and formative principle to individual creatures. Paracelsus endowed Ares with a watery character, bringing it into relationship to the body. The Paracelsan concept of Ares is seen to be scarcely distinguishable from that of Aquaster, a situation not uncommon in alchemy where concepts are seen to take the place of one another ad infinitum.
http://www.cgjungcenterphiladelphia.org/