Silene acaulis, known as moss campion or cushion pink, is a small mountain-dwelling wildflower that is common all over the high arctic and tundra in the higher mountains of Eurasia and North America, (south to the Alps, Carpathians, southern Siberia, Pyrenees, British Isles, Iceland, Faroe Islands, Rocky Mountains). It is an evergreen perennial flowering plant in the carnation family Caryophyllaceae. It is also called the compass plant, since the flowers appear first on the south side of the cushion. (Various other plants also have this name.)