208 



Mycologia 



persistens. Asci fixi. — Stipes constanter praesens, cum centro 

 receptaculi contiguus, cavus 1. medulla floccosa farctus. Pileus 

 adultus mitraeformis, compressus, lobatus, siccus, subtus pru- 

 inosus. Substantia eeraceo-membranacea. 



Plants large, usually several centimeters high, stipitate and 

 upright. Pileus thin, deflexed, attached at the center, concave 

 below ; of irregular shapes, lobed, irregularly undulate, mitri-. 

 form, compressed, saddle-shaped, etc. ; not typically cup-shaped 

 or closed when young ; without gyrose elevations on the upper 

 surface; margin free or attached to the stipe on opposite sides 

 or at several points ; of a waxy membranaceous or waxy-fleshy 

 consistency ; upper surface covered by the hymenium, glabrous ; 

 lower surface sterile, glabrous, pruinose, tomentose or villose, 

 sometimes rugulose or venose. Hypotheci'um and excipulum of 

 densely interwoven hyphae passing outwardly into a pseudo- 

 parenchymatous cortex of larger cells. Stipe slender or stout ; 

 straight or irregularly undulate ; smooth, lacunose or with deep 

 longitudinal furrows separated by narrow costae, frequently en- 

 tire stipe composed of costae united by their inner edges, outer 

 edges of costae usually irregularly anastomosing ; solid, stuffed 

 or hollow ; glabrous, pruinose, tomentose or villose. Asci long 

 cylindrical or narrowly clavate, with 8 spores in a single row. 

 Spores hyaline, continuous, ellipsoidal, smooth, 15-20 X 9-1 2/x, 

 in our species, with a large prominent central oil globule. Para- 

 physes slender, straight, septate, sometimes branching, enlarging 

 upward to 2-3 times the diameter of the base, hyaline or tinged 

 with brown. 



Solitary or gregarious, subfleshy fungi, without distinctive taste 

 or odor, autumnal, in the damp woods on the ground or wet 

 rotten stumps or logs. Most of them are said to be edible. 



The genus as originally delimited by Fries (1823) falls natur- 

 ally into three sections, as follows : 



Stipe longitudinally sulcate-costate (fluted). Helvella proper 



Stipe smooth, or at most somewhat lacunose or irregular. 



Small plants with slender stipes. Leptopodia Boud. 



Large plants with thick stipes. Gyromitra Fries 



The first section is the oldest and best known and is typified 

 by the common species H. crispa and H. lacunosa. These species 

 have never been referred to any other genus since the time of 

 Fries. 



The second section includes H. elastica, H. atra, H. ephippium 

 and H. adhaerens. It includes the species on the doubtful line 



