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 their cousins' herd. Idas and Lynceus eventually set out for home, leaving Helen alone with Paris, who then kidnapped her. Thus, the four cousins helped set into motion the events that gave rise to the Trojan War. Meanwhile, Castor and Pollux had reached their destination. Castor climbed a tree to keep a watch as Pollux began to free the cattle. Far away, Idas and Lynceus approached. Lynceus, named for the lynx because he could see in the dark, spied Castor hiding in the tree. Idas and Lynceus immediately understood what was happening. Idas, furious, ambushed Castor, fatally wounding him with