1) Fern genus 2) Genus pilularia 3) Pillworts 
Pilularia or pillworts is a genus of unusual ferns of family Marsileaceae distributed in North Temperate regions, Ethiopian mountains, and the southern hemisphere in Australia, New Zealand, and western South America. Depending on the taxonomic revisor, the genus contains between 3 and 6 species of small plants with thread-like leaves, and creeping...
[n] - pillworts
genus Pilularia noun pillworts