Hornwrack Flustra foliacea
Hornwracks are often mistaken for a brown seaweed. The colony grows up from a narrow base as thin, flat, fan-like lobes. These usually form dense clumps and cover the sea bed like a crop of tiny brown lettuces. Hornwrack colonies litter the strandline on many shores in dried clumps and, by using a magnifying glass, an observer can easily see the individual, oblong colony members.