1911 Encyclopædia Britannica/Dulse
DULSE (Ir. and Gael, duileasg), in botany, Rhodymenia palmata, one of the red seaweeds, consisting of flat solitary or tufted purplish-red fronds, fan-shaped in general outline and divided into numerous segments, which are often again and again divided in a forked manner. It varies very much in size and degree of branching, ranging from 5 or 6 to 12 or more inches long. It grows on rocks, shell-fish or larger seaweeds, and is used by the poor in Scotland and Ireland as a relish with their food. It is commonly dried and eaten raw, the flavour being brought out by long chewing. In the Mediterranean it is used cooked in ragouts and made dishes.
See W. H. Harvey, Phycologica Britannica, vol. ii. plates 217, 218.