This section is from the book "Studies of American Fungi: Mushrooms, Edible, Poisonous, Etc.", by George Francis Atkinson. Also available from Amazon: Studies of American Fungi: Mushrooms, Edible, Poisonous, Etc..
The helvellas are pretty and attractive plants. They are smaller than the morels, usually. They have a cap and stem, the cap being very irregular in shape, often somewhat lobed or saddle-shaped. It is smooth, or nearly so, at least it is not marked by the large pits present in the cap of the morel, and this is one of the principal distinguishing features of the helvellas as compared with the morels. In one species the thin cap has its lower margin free from the stem. This is Helvella crispa Fr., and it has a white or whitish cap, and a deeply furrowed stem. It occurs in woods during the summer and autumn, and is known as the white helvella.
Helvella lacunosa (natural size). Copyright.
Another species which has a wide range is the Helvella lacunosa. so called because of the deep longitudinal grooves in the stem. The cap is thin, but differs from the H. crispa in that the lower margin is connected with the stem. This species is illustrated in Fig. 219 from plants collected at Blowing Rock, N. C, during September, 1899.
The genus Gyromitra is very closely related to Helvella, and is only distinguished by the fact that the cap is marked by prominent folds and convolutions, resembling somewhat the convolutions of the brain. Its name means convoluted cap. The Gyromitra esculenta Fr., is from 5-10 cm. high, and the cap from 5-7 cm. broad. While this species has long been reported as an edible one, and has been employed in many instances as food with no evil results, there are known cases where it has acted as a poison. In many cases where poisoning has resulted the plants were quite old and probably in the incipient stages of decay. However, it is claimed that a poisonous principle, called helvellic acid, has been isolated by a certain chemist, which acts as a violent poison. This principle is very soluble in hot water, and when care is used to drain off first water in which they have been cooked, squeezing the water well from the plants, they are pronounced harmless. The safer way would be to avoid such suspicious species.
Spathularia velu-tipes Cooke & Farlow. - This species represents another interesting genus of the Discomycetes. It is in the form of a "spatula," and from this shape of the plant the genus takes its name. There are several species known in this country, and this one is quite common. The stem extends the entire length of the plant, running right through the cap, or perhaps it would be better to say that the cap or fruiting portion forms two narrow blades or wings on opposite sides of the upper part of the stem. These wing-like expansions of the cap on the opposite sides of the stem give the spathu-late form to the plant. Figure 220 is from plants collected in the woods near Ithaca.
Spathularia velutipes (natural size). Copyright.
Leotia lubrica (natural size). Copyright.
The genus Leotia is quite readily recognized by its form, and because the plants are usually slimy. This species is called lubrica because of the slippery character of the entire plant. It is dull yellowish or olive yellow in color. The cap, as can be seen from the figure (221), is irregularly rounded, and broader than the stem. The plant is illustrated natural size from specimens collected near Ithaca.