  A hyperbolic flux-tube configuration containing a null point below the flux
rope is considered as a pre-eruptive state of coronal mass ejections that start
simultaneously with flares. We demonstrate that this configuration is unstable
and cannot exist for a long time in the solar corona. The inference follows
from general equilibrium conditions and from analyzing simple models of the
flux-rope equilibrium. A direct consequence of the stable flux-rope equilibrium
in the corona are separatrices in the horizontal-field distribution in the
chromosphere. They can be recognized as specific "herring-bone structures" in a
chromospheric fibril pattern.
