  An experimental study of magnetic flux penetration under crossed magnetic
fields in Bi2212:Pb single crystals is performed by the magneto-optic
technique. The anisotropy of the flux creep rate induced by the in-plane
magnetic field is observed at $T<54\pm 2$ K. This observation confirms the
existence of the three-dimensional flux line structure in Bi2212:Pb at low
temperatures. An asymmetry of the flux relaxation with respect to the direction
of the in-plane field is found. This effect can be attributed to the influence
of the laminar structure on the pinning in Bi2212:Pb single crystals.
