Bifurcated stem foam pump

A bifurcated stem foam pump for use in foam dispensers. An air compressor portion of the bifurcated pump is attached to and maintained as a portion of the dispenser housing. A portion of the pump for transferring liquid and including a portion for generating foam is attached to and provided as a portion of a replaceable liquid-containing cartridge in the foam dispenser. The two portions mate and form a completed pump assembly operative for generating foam from the liquid of the cartridge when the cartridge is placed within the dispenser housing and the two pump portions are mated. The air compressor portion includes a collar having an air piston reciprocatingly received therein. The collar is attached to the dispenser housing. A collar receiving a hollow stem pump is attached to the liquid cartridge. Actuation of the air piston correspondingly actuates the stem pump such that air and liquid are forced together in the stem pump and through a foam generating member.