Ammit
(Ammut Ahemait)
An
Egyptian demon; sometimes clearly female and human, sometimes
with the head of a crocodile, the torso of a wild cat and
the hindquarters of a hippopotamus.
Ammit
("devouress of the dead") sits under the Scales of Justice,
in the Hall of the Two Truths, in the House of Osiris.
When
a person dies and after performing the necessary rituals,
he is taken there by Anubis, in
his role as psychopomp ("conductor of souls"), to be weighed.
Here he will have a chance to defend his deeds in his previous
existence.
The
role of the prosecutor is for Thoth,
the god of wisdom. Osiris sits on his throne as the judge,
accompanied by the goddesses Isis
and Nephthys.
Eventually
the heart of the deceased will be placed on one of the scales
and a feather, from the headband of Ma'at
the goddess of truth on the other. If the heart under the
weight of its sins, weights more than the feather, then
Ammit will appear from underneath the scales to devour it.
This means the end of the soul and there will be no chance
for a further existence.
The
name of Ammit in hieroglyphs: 
The
Encyclopedia Mythica