Both of these plants are liverworts. Liverworts are different from most other plants described in this manual in that they lack vascular tissues for transporting water and nutrients within their bodies. They are small, many less than 2 cm, and lack stems, flowers, and roots. The name "liverwort" dates back to the ninth century when it was thought the liver-shaped plants might be useful in treating liver diseases.

Stem: None.

Flower: None.

Fruit: None. Microscopic spores are produced in tiny spore-producing organs embedded within the thallus.

Root: Fine, root-like structures (rhizoids) absorb water and nutrients, and sometimes anchor the plants. Slender riccia: few if any, white rhizoids. Purple-fringed: numerous brownish purple rhizoids.

Propagation: Spores and budding (a new plant forms from a vegetative outgrowth of a mature plant).

Importance of plant: Food for ducks and birds; provides habitat for aquatic insects and invertebrates.

Distribution: Both occur nearly worldwide.

Habitat: Mostly floating in sheltered shallow water of ponds, pools, and swamps that tend to be warm or nutrient enriched. Sometimes stranded and anchored along shorelines. Often found growing with duckweeds (Lemna sp., Spirodela sp.) and Mexican water-fern (Azolla mexicana).

May be confused with: Duckweeds (Lemna, Spirodela) and Mexican water-fern (Azolla mexicana). These species do not have the twice-branched, ribbon-like leaves of slender riccia, or the purple rhizoids of purple-fringed riccia.

Photographs: Closeup of Ricciocarpus natans

Line Drawings: Ricciocarpus natans, Riccia fluitans