Trans. Br. Mycol. Soc. 85(4): 699-707, 1985.

Ascomata 950-1240 mm high, 945-1500 mm dia., 240-476 mm thick, subglobose, laterally compressed, completely or partially immersed in a black stroma, with a longitudinal furrow at the top, carbonaceous to coriaceous, black, gregarious.

Asci 450-570 x 26-38 mm, 8-spored, cylindrical, fissitunicate, long pedunculate, thick walled, with a refractive apical plate in the ectoascus and a refractive apical ring in the endoascus, ring not staining blue in IKI.

Ascospores 76.0-102.0 x 17.0-22.5 mm, biseriate, ellipsoidal to broadly fusiform, muriform, with 14-17 (-18) transverse septa and 1-3 longitudinal septa in all but the end cells, slightly constricted at the septa, yellow-brown except for the hyaline or light brown apical cells, glabrous, with a gelatinous cap, 2.5-3 mm thick, around the apical and sub-apical cells.