A dosing bottle closure (24) has a body (26) and a lid (27). The body (26) has: a sidewall (50) extending from a lower rim (54) to an upper rim (62); and means (58) along the sidewall (50) for engaging a container body (22). The lid (27) is hinged relative to the body for articulation between a closed condition and an open condition. The body defines an internal upwardly open chamber (25) at least partially covered by the lid in the closed condition. The body defines a feed passageway (100) having an outlet (110) to the chamber (25) and spaced above a bottom (72) of the chamber and defines a vent conduit (300).