Common Bonnet (Mycena galericulata). Mycena galericulata is a mushroom commonly known as the common bonnet, the toque mycena, or the rosy-gill fairy helmet. It is quite variable in color, size, and shape, which makes it somewhat difficult to reliably identify in the field. The mushrooms have caps with distinct radial grooves, particularly at the margin. The cap's color varies from grayish-brown to dark brown and the shape ranges from bell-like to bluntly conical to flattened with an umbo. The stem is hollow, white, tough and thin, without a ring and often roots deeply into the wood on which it grows. The gills are white to grayish or even pinkish when mature and are connected by distinct cross-veins. Fungi; Basidiomycota; Agaricomycetes; Agaricales; Mycenaceae; Mycena; galericulata .