It is well known that when a suspension of noncolloidal, neutrally buoyant rigid particles is drawn into an empty tube, the inward shear-induced migration of the particles results in a continuously growing packed layer of particles at the advancing meniscus. For non-neutrally buoyant suspensions, however, gravity perpendicular to the flow direction modifies the fully developed concentration profile and can lead to depletion of particles at the meniscus. This accumulation/ depletion phenomenon was studied experimentally as a function of the buoyancy number N-b, the ratio of gravitational to viscous forces. The rate of accumulation or depletion was used to determine the area average concentration as a function of Nb and the feed concentration. These results are in good agreement with the profiles calculated theoretically using the suspension balance model of Nott and Brady.