Destroying angels are characterized by having a white stalk and gills. The cap can be pure white, or white at the edge and yellowish, pinkish, or tan at the center. It has a partial veil, or ring (Annulus) circling the upper stalk, and the gills are "free," not attached to the stalk. Perhaps the most telltale of the features is the presence of a volva, or universal veil, so called because it is a membrane that encapsulates the entire mushroom, rather like an egg, when it is very young. This structure breaks as the young mushroom expands, leaving parts that can be found at the base of the stalk as a boot or cuplike structure, and there may be patches of removable material on the cap surface. This combination of features, all found together in the same mushroom, is the hallmark of the family. While other families may have any one or two of these features, none have them all. The cap is usually about 5–12 cm across; the stem is usually 7½–20 cm long and about ½–2 cm thick. They are found singly or in small groups.
Destroying angels can be mistaken for edible fungi such as the button mushroom, meadow mushroom, or the horse mushroom. Young destroying angels that are still enclosed in their universal veil can be mistaken for puffballs, but slicing them in half longitudinally will reveal internal mushroom structures. This is the basis for the common recommendation to slice in half all puffball-like mushrooms picked when mushroom hunting. Mushroom hunters recommend that people know how to recognize both the death cap and the destroying angel in all of their forms before collecting any white gilled mushroom for consumption.
"Physicians have had success in treatment of amatoxin poisoning using "anti-hepatotoxic" compounds from the milk thistle, Silybum marianum. A crude extract of flavolignans from S. marianum seeds, called silymarin (trade name Legalon) has proven useful in amatoxin poisoning cases. In a recent trial of one of the flavolignans silybin, in 60 patients poisoned by amatoxin-containing Amanita species, there were no deaths. (see Der Marderosian & Liberti 1988 and Foster 1991 for a summary of this work).