  It is shown that the carrier of a bounded localized free Dirac wavefunction
shrinks from infinity and subsequently expands to infinity again. The motion
occurs isotropicly at the speed of light. In between there is the phase of
rebound, which is limited in time and space in the order of the diameter of the
carrier at its minimal extension. This motion proceeds anisotropicly and
abruptly as for every direction in space there is a specific time, at which the
change from shrinking to expanding happens instantaneously. Asymptotically,
regarding the past and the future as well, the probability of position
concentrates up to 1 within any spherical shell whose outer radius increases at
light speed.
