German legend, "a shepherd, who was driving his flock over the
Ilsenstein, having stopped to rest, leaning on his staff, the
mountain suddenly opened, for there was a springwort in his
staff without his knowing it, and the princess [Ilse] stood
before him. She bade him follow her, and when he was inside
the mountain she told him to take as much gold as he pleased.
The shepherd filled all his pockets, and was going away, when
the princess called after him, 'Forget not the best.' So,
thinking she meant that he had not taken enough, he filled his
hat also; but what she meant was his staff with the
springwort, which he had laid against the wall as soon as he
stepped in. But now, just as he was going out at the opening,
the rock suddenly slammed together and cut him in two."[26]

[26] Kelly, Indo-European Folk-Lore, p. 177.

Here the rod derives its marvellous properties from the
enclosed springwort, but in many cases a leaf or flower is
itself competent to open the hillside. The little blue flower,
forget-me-not, about which so many sentimental associations
have clustered, owes its name to the legends told of its
talismanic virtues.[27] A man, travelling on a lonely
mountain, picks up a little blue flower and sticks it in his
hat. Forthwith an iron door opens, showing up a lighted
passage-way, through which the man advances into a magnificent
hall, where rubies and diamonds and all other kinds of gems
are lying piled in great heaps on the floor. As he eagerly
fills his pockets his hat drops from his head, and when he
turns to go out the little flower calls after him, "Forget me
not!" He turns back and looks around, but is too bewildered