setalg laminaria digitata is a brown seaweed belonging to the laminariale species. its glossy brown thallus can reach 3 to 4 m in length. it has a cylindrical, smooth, flexible stipe and a thallus divided into laminae. its thallus is fixed to the rocks near or below the low tide level down to a depth of 10 m. this type of seaweed is considered to be the most advanced anatomically. laminaria has ...