A small red alga (up to 8 cm in length), it is tough and cartilaginous with flattened fronds. Branching is alternate and occurs in one plane only, with branches becoming shorter towards their apex and broadly rounded. The plant is highly variable in size and colouration depending upon its location on the shore. Higher shore plants are generally dwarfed and yellow-green in colour, owing to exposure to high levels of sunshine while on the lower shore they are reddish-brown.This aromatic seaweed is dried and used as a spice in Scotland.