How to tell Grey shag from Magpie inkcap

The cap is small, 1 to 5 centimetres tall, egg-shaped or bell-shaped at first; with age it opens out and dissolves into inky liquid from the margin. The surface is grey to ash-grey, often covered with small whitish scales or a mealy coating left by the veil. Young caps are paler; as they mature they grey and blacken from the edges. The whole cap is thin and pleated-striate.

The young cap is egg-shaped, 5 to 8 cm tall, and completely covered in a white, sometimes greyish or cream, felty veil. As it opens it becomes bell-shaped, 4 to 8 cm across and occasionally up to 10 cm, and the veil breaks into separate white patches on a dark brown to almost black, glossy background.

With age the margin rolls upwards and dissolves into black liquid from the edge inwards.

The gills are free and very crowded, whitish at first, then quickly blackening and dissolving into inky liquid along with the cap margin (autolysis). The spore print is black. Rapid self-digestion of the gills into ink is characteristic of all ink caps.

The gills are free and very crowded. They start white, turn pinkish or wine-tinged, then grey and black, and finally dissolve into black ink.

The spore print is black.

The stem is thin, hollow, white or whitish grey, up to 10 centimetres tall and smooth, often with a slightly thickened base. Usually there's no ring, or just a trace of the veil, and there's no volva. Fragile and thin, it's typical of small ink caps.

The stem is 10 to 20 cm tall, sometimes up to 30 cm when it grows up through deep leaf litter, and 0.5 to 1.5 cm thick. It's white, hollow and fragile, tapering slightly upwards, with a small woolly swelling at the base.

There's usually no ring, but the shaggy inkcap often loses its ring too, so the dark cap skin is the better guide.

The flesh is extremely thin, greyish or whitish, with no particular taste. Because of rapid autolysis it doesn't last: within a few hours of maturing, the fruiting body dissolves. It has almost no culinary value.

The flesh is thin, fragile, white and watery, and doesn't change colour when cut.

The smell is faint and nondescript, mushroomy or slightly musty, and isn't a defining feature. You recognise this mushroom by its grey, pleated cap that dissolves into ink, its black gills and its habit of growing on dung, compost and fertilised soil.

The smell is sometimes unpleasant, of tar, mothballs or carbolic, and sometimes not distinctive. Don't taste it.