A plant of C. racemosa consists of a number of branches linked to stolons which are anchored to the sandy substrate by rhizoids. The branches are a few centimetres apart and can grow to a height of 30 centimetres (12 in). Many spherical or ovate side-shoots branch off these and give the seaweed its name of sea grapes. Like other members of the order Bryopsidales, each C. racemosa plant consists of a single enormous cell with a large number of nuclei.