Marginal cystidia: spindle-shaped and crested with crystals.
General Information: This fungus is often buried to half-way in the sand of slacks near dwarf willows (Salix spp.). Three other species of Inocybe grow in dune-slacks I. halophila Heim, I. serotina Peck and I. devoniensis P. D. Orton, but all differ in their spores being smooth and elongate-cylindric. Astrosporina, a name referring to the shape of the spore, has been considered a genus of agarics in its own right and to this group I. dunensis would belong. However, as the members show the same range of characters as those species with the smooth spores it seems unnecessary to split Inocybe into two. The cystidia in many species are unusual, being crested with a bundle of crystals which have been reported as being calcium oxalate, although even the simplest school-laboratory tests have been rarely applied to them (see [p. 84]).
Plate 79. Sand-dune fungi
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Psathyrella ammophila (Durieu & Léville) P. D. Orton Sand-dune brittle-cap
Cap: width 20-40 mm. Stem: width 4-8 mm; length 40-80 mm.
Description: [Plate 79].
Cap: semiglobate to convex, pale dingy clay-colour or dark tan to dirty brownish, non-striate, rather fleshy and usually sand covered.
Stem: deeply rooting in sand and club-shaped towards the base, similarly coloured to the cap except for the whitish apex.