Marchantia is the most common of the liverworts, often a greenhouse weed.  Liverworts have no true leaves, roots, or stems.  They do not have flowers or seeds.  The part you see mostly look like a mat of flat "leaves", it is called a thallose.

A closer view of the thallose with gemma cups, mostly empty.

These cups still have gemmae in them.  Water drops falling into a cup will splash the gemmae out.  Each gemma then grows into a new thallose. This is a form of asexual reproduction.

Here are some female reproductive structures for sexual reproduction

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