A stamen is composed of an anther and a filament. The stamen is the male reproductive organ of the flower. The stalk of a stamen is the filament and on top of the filament is the anther. The anther contains microsporangia which produces haploid spores. The haploid spores divide by mitosis and form immature microgametophytes, or pollen grains. The collection of stamens in a flower is called the androecium. The androecium surrounds the gynoecium (collection of carpels) and is located inside the perianth (petals and sepals). The fusion of multiple filaments is an androphore. In the flower pictured, there are five stamens.