(Either these two are the same, or they're still confounded. I couldn't find any botanical references to "Iridea edulis", though. -Henriette.)
Iridea edulis Bory. Algae.
"It is an unaccountable fact that this plant should have been long confounded with Rhodymenia palmata — the true Irish eatable Dulse. I have never seen I. edulis eaten, but Stackhouse tells us that in Cornwall it is sometimes eaten by fishermen, who crisp it over the fire."