back to Blackness or Nigredo
Putrefaction, the process during the phase of blackness. Again a skeleton and a black raven. The cut off tree stump to the right is a symbol that sometimes appears in alchemical engravings to symbolize that the old self has to be cut off and a new self will spring up (the new growth symbolized by the fresh sprout on the trunk).
The skeleton is standing on an eclipsed sun. The sun is the Inner Sun, the divine Self, that is hidden by the blackness of our every day, normal behavior and being. It is obscured by the physical consciousness we all have. Therefore that what obscured our divine Self has to be putrefied and purified in order for the divine Self to chine in all its glory.