Charge retention in deep-inelastic electroproduction

We have measured the net charge of the forward hadrons electroproduced from a proton target and have observed a rise with increasing x ( = Q/sup 2//2M..nu..). This effect is expected in the quark-proton model as the electroproduction of hadrons becomes dominated by the fragmentation of u quarks. The data are also consistent with jet models in which a high-momentum leading hadron, rather than a slower hadron, is more likely to be carrying the parent quark.