uphantænia

from The Century Dictionary.

• noun A generic name given by Vanuxem to a fossil from the Chemung group in New York, of very problematic character, classed by Schimper with Dictyophyton in a group of Algæ to which he gave the name of Dictyophyteæ: but at the same time he calls attention to the fact that this most extraordinary fossil possesses some of the characters of the skeleton of a silicious sponge, and it has been recently more generally referred to this class of organisms. See Dictyophyton.