(The). If you look at a leaf of myrtle in a strong light, you will see that it is pierced with innumerable little punctures. According to fable, Phædra, wife of Theseus fell in love with Hippolotus, her step-son; and when Hippolotus went to the arena to exercise his horses, Phædra repaired to a myrtle-tree in Troezen to await his return, and beguiled the time by piercing the leaves with a hair-pin. The punctures referred to are an abiding memento of this tradition.
In the Orlando Furioso Astolpho is changed into a myrtle-tree by Acrisia.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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