Five New Hypogaeous Fungi

Abstract

Ascocarp light yellowish-gray, with wide white venae externae conspicuous on surface, 1.8-5.5 cm. in diameter, sub-globose, much convoluted; surface very minutely scabrous; gleba light chocolate colored at maturity, marbled with distinct shining white veins varying in width, older specimens containing several large fissures from breaking along venae externae; venae externae rarely converging at a distinct point; outer layer of cortex pseudoparenchymatous, changing to loose hyphal tissue which gradually merges into sub-cortical layer of more slender hyphae; thickness from the surface to the hymenium 220-260 ll; venae internae and hymenial tissue similar to structure of the subcortex; venae externae of loosely arranged hyphae, breaking away at maturity to form fissures; asci not stipitate, semi-globose, 52-70 x 74-80 ll, 1-4(rarely 5-) spored; spores dark yellowishbrown, ellipsoid or ovoid, 17-39 x 35-52 lx, alveolate, 5-9 x 7-10 alveoli across the diameters, these varying somewhat in size on a single spore; also apparently very minute alveoli on inner surface of epispore; sculpturing 2-3 ll in height. (Plate 26, Fig. 1.) Collected in clay soil under trees and shrubs, by John Sert, at Bandon, Oregon, May 2, 1921. This is, to my knowledge, the largest Tuber reported from the United States, several specimens of the collection reaching 5.5 cm. in diameter. Mr. Sert discovered the fruiting bodies from several inches to a foot deep in a clay hillside which was being graded for a road bed. The spores are long-ellipsoid like those of Tuber gibbosum Hark., but are rounded rather than pointed at the ends and are generally smaller. The ascocarp of T. gibbosum is cinnamon-brown rather than yellowish-gray; the surface is covered with knotty hairs which are absent in the above described species; and the inner surface of the epispore does not show the secondary sculpturing described above.