The Los Alamos/Garching fast plasma experiments on ISEE 1 and 2 detected a large number of accelerated flow events at the near-tail dusk magnetopause separating the plasma sheet from the magnetosheath. Such events are common when the local magnetosheath and plasma sheet magnetic fields are nearly antiparallel, and they can persist for hours at a time. Accelerated plasma flows at the near-tail magnetopause are observed only within the current layer where the field rotates from its magnetosheath to its magnetotail orientation and are characterized by (1) tailward directed flow at speeds up to ~2 times faster than observed in the adjacent magnetosheath, (2) densities comparable to but slightly lower than those in the magnetosheath, and (3) ion and electron temperatures intermediate between magnetosheath and plasma sheet values. The highest flow speeds and the lowest densities within the current layer typically occur near the inside edge. A thin region of density-depleted field lines often exists immediately earthward of the accelerated flow region. The observed velocity changes at the magnetopause are in rough agreement with tangential stress balance, and we interpret these flows as direct evidence for field line merging near and perhaps tailward of the dawn-dusk terminator. Accelerated flows are much more rare at the dawn tail magnetopause in the ISEE data. This dawn-dusk asymmetry may be an artifact associated with a seasonally dependent warping of the midtail neutral sheet. A more likely explanation is that the asymmetry is caused by the preferred draping of the interplanetary magnetic field about the dusk magnetopause.