Salicylaldehyde be prepared from the corresponding phenol by the Duff reaction, or by treatment with paraformaldehyde in the presence of magnesium chloride and a base. Salicylaldehyde was identified as a characteristic aroma component of buckwheat. It is also one of the components of castoreum, the exudate from the castor sacs of the mature North American beaver ("Castor canadensis") and the European beaver ("Castor fiber"), used in perfumery. Furthermore, salicylaldehyde occurs in the larval defensive secretions of several leaf beetle species that belong the subtribe Chrysomelina. An example for a leaf beetle species that produces salicylaldehyde is the red poplar leaf beetle
Castor and Pollux her. In revenge they abducted Theseus's mother Aethra and took her to Sparta while setting his rival, Menestheus, on the throne of Athens. Aethra was then forced to become Helen's slave. She was ultimately returned to her home by her grandsons Demophon and Acamas after the fall of Troy. Castor and Pollux aspired to marry the Leucippides ("daughters of the white horse"), Phoebe and Hilaeira, whose father was a brother of Leucippus ("white horse"). Both women were already betrothed to cousins of the Dioscuri, the twin brothers Lynceus and Idas of Thebes, sons of Tyndareus's brother Aphareus. Castor and Pollux