rhizina

from The Century Dictionary.

• In botany, same as rhizoid.
• noun [capitalized] A genus of discomycetous fungi having fleshy, flat, spreading ascocarps frequently becoming irregular and provided with cylindrical root-like strands of mycelium below. The spores are unicellular and colorless. Eight species have been described. R. inflata occurs on burned places in woods and is suspected of being the cause of certain root diseases of forest trees, especially pines. It is widely distributed in Europe, Asia, and North America.