Myxomycetes

The myxomycetes (plasmodial slime molds) are a group of fungus-like organisms usually present and sometimes abundant in terrestrial ecosystems. The myxomycete life cycle involves two very different trophic (feeding) stages, one consisting of uninucleate amoebae, with or without flagella, and the other consisting of a distinctive multinucleate structure, the plasmodium.

Myxomycete plasmodia typically occur in cool, moist, shady places such as within crevices of decaying wood, beneath the partially decayed bark of logs and stumps, and in leaf litter on the forest floor. Under favorable conditions, the plasmodium gives rise to one or more fruiting bodies containing spores. The spores of myxomycetes are for most species apparently wind-dispersed and complete the life cycle by germinating to produce the uninucleate amoeboflagellate cells.

References:

1) http://www.myxoweb.com/what.htm
2) http://www.discoverlife.org/20/q?search=Eumycetozoa