Phylum: Rhodophyta   Family: Wrangeliaceae

Plumaria plumosa (Hudson) Kuntze, 1891

Soft Feather Weed

Dark red at the corticated base, lighter in the mid-sections, with brownish-grey incurved ramuli at the apices. Common on lower inter-tidal rocks

References: 
Fish & Fish (2011) - A Student's Guide to the Seashore;
Bunker, et al - Seaweeds of Britain and Ireland;
Hiscock (1986) - A Field Key to the British Red Seaweeds