BRIEF DESCRIPTION: This description is based on dried and fresh material collected or reviewed by the author.

The cap of Amanita vaginata var. alba is 30 - 100^± mm wide, hemispheric at first, very finely rugose at first, shining, greasy, nonappendiculate, with slightly incurved and striate margin (with striations occupying 20 - 30% of the radius); it is white to ivory becoming somewhat sordid with age. The flesh is white.  The volva is usually absent; it is sometimes present as more or less membranous patches of greatly varying size.

The gills are free, narrowly adnate, or connected by line, crowded, white or very pale pinkish cream, with a fimbriate edge.  The short gills are unevenly distributed, of diverse lengths, and plentiful.

The stem is 47 - 130 x 4 - 15 mm, white or pale cream or pale tan, narrowing upward or subcylindric, and exannulate.  The flesh is white, brownish at the very base, and hollow.  The saccate volva is externally white, with inner surface whitish; and it is membranous and smooth.  It seems to be somewhat weakly structured and rather often exhibits very uneven limbs at the stem base or the basal part is separate from all or part of the remainder.  As noted above, substantial portions of the volva may be removed and carried away by the expanding stem and cap.  Infrequently only a cupulate remnant remains at the very base of the stem.

The spores measure (8.6-) 9.8 - 12.8 (-17.0) x (7.0-) 8.5 - 12.0 (-13.5) µm and are globose to subglobose (infrequently broadly ellipsoid, rarely ellipsoid) and inamyloid.  Clamps are not observed at bases of basidia.

This species is known from Birch associations in northern Europe (for example, Scotland and Norway) and Greenland.  Whether this taxon is the same as A. vaginata var. alba sensu Japanese authors or var. alba sensu American authors is not yet known.  The volva in the latter also seems rather easily fragmented.

It is most closely related to the group containing at least some of the brownish gray or grayish brown entities included in Amanita vaginata sensu European authors as well as A. atrofusca Zhu L. Yang, A. lignitincta Zhu L. Yang, A. orientifulva Zhu L. Yang, M. Weiss & Oberw., and A. umbrinolutea var. flaccida D. A. Reid. -- R. E. Tulloss