A dispensing system for a liquid or viscous treating agent for use with a washing machine with a suds container configured to receive wash liquid. The dispensing system includes a dispenser box in communication with a water feed line. The dispenser box is configured to dispense treating agents to the suds container by flushing the treating agents out from the dispenser box. A receiving compartment is disposed in the dispenser box and is configured to receive a cartridge for holding a supply of the liquid or viscous treating agent. A dosing device configured to dispense the treating agent from the cartridge to the suds container is included in the dispensing system. The dosing device includes a linear displacement pump disposed on the cartridge. The linear displacement pump is configured to dispense a substantially constant volume of the treating agent from the cartridge with each stroke. The substantially constant volume of treating agent is a fraction of a total volume of treating agent for dispensing.