The purpose of this paper is to discuss the properties of electron beams formed by cyclotron interactions between radiation belt electrons and a quasi-monochromatic whistler wave packet from a ground-based VLF transmitter. The beams are formed due to trapping of the electrons at the forward edge of the wave packet, their acceleration inside the wave packet, the escape of the accelerated electrons from the moving backward edge of the wave packet, and their following free motion in an inhomogeneous magnetic ยฎeld. A combination of these processes provides the main features of the spatial-temporal evolution of the beams which are investigated both analytically and numerically. It is shown that one or two beams can appear at one point at the same time, and that the density of the beams increases during their expansion. Motion of the pumping wave packet in the inhomogeneous magnetic ยฎeld provides the variations of the initial velocity and position of the beam injection which change the spatial and temporal gradients of the parallel velocity of the beam, in contrast with the case of the pure adiabatic motion of an individual electron. Such a behaviour can be signiยฎcant for the generation of secondary emissions. Numerical calculations demonstrate a wide variety of the spatioยฑtemporal patterns of the beam parallel velocity depending on the plasma and wave packet parameters. It is shown that the most signiยฎcant parameters which determine the beam characteristics are the wave packet length about the equator, its group velocity, and the initial energy and pitch angle of the electrons.