Ceramiaceae is a family of cellular sea-weeds (Algae) consisting of thread-like jointed plants of a red or brown-red colour. The spores are in masses in transparent membranous sacs, and the tetraspores are external. The Chondrus crispus, or carrageen moss; the Rhodomenia palmata, or dulse; and the Plocaria tenax, extensively used by the Chinese as ...