Three dimensional vector field map, in Galactic cartesian coordinates, of the 616 members with a radial velocity in Gaia DR2. The members of the subgroups are colored (see inset). The black arrow shows the median motion of all members. The sources highlighted by red circles and arrows have ΔV ≥ 0.75 and orange diamonds have cos(v_obs, v_p) ≤ 0.8, and are potential interlopers. Most of them meet both conditions except four.