xanthidium

‖n.; pl. Xanthidia [ NL., fr. Gr. xanqo`s yellow. ] (Bot.) A genus of minute unicellular algae of the desmids. These algae have a rounded shape and are armed with glochidiate or branched aculei. Several species occur in ditches, and others are found fossil in flint or hornstone. [ 1913 Webster ]