Irish Moss

Also called  Carrageen  (Chondrus crispus), species of red algae, a small, tufted seaweed with thin fronds from 5 to 25 cm (2 to 10 inches) long, that grows abundantly along the rocky parts of the Atlantic coast of the British Isles, Europe, and North America. The name is also used loosely for several other red seaweeds found associated with Chondrus. Other names descriptive of its appearance are pearl moss,