Haircap moss

Description:

Like all mosses, the green plant that you see is the gametophyte (haploid) generation. These plants produce eggs and flagellated sperm by mitosis (not meiosis) in specialized organs called archegonia and antheridia, respectively. Unlike most plants other than ferns, moss sperm is flagellated and must swim in water to reach an egg. Most mosses hold their reproductive organs in structures known as splash cups. When a raindrop hits a splashcup, gametes splash out in much the same way water sprays everywhere when you wash a spoon in fast-running water. When a sperm reaches an archegonium, it can swim to fertilize an egg. The resulting diploid plant, the sporophyte, is the tiny cattail-looking structure sticking out of patches of moss.