Castoreum Castoreum Castoreum is a yellowish exudate from the castor sacs of the mature North American beaver ("Castor canadensis") and the European beaver ("Castor fiber"). Beavers use castoreum in combination with urine to scent mark their territory. Both beaver sexes have a pair of castor sacs and a pair of anal glands, located in two cavities under the skin between the pelvis and the base of the tail. The castor sacs are not true glands (endocrine or exocrine) on a cellular level, hence references to these structures as preputial glands, castor glands, or scent glands are misnomers. It is used as
Castor and Pollux of Tyndareus alone, but they were sons of Zeus in the Hesiodic "Catalogue" (fr. 24 M-W). The conventional account (attested first in Pindar, Nemean 10) combined these paternities so that only Pollux was fathered by Zeus, while Leda and her husband Tyndareus conceived Castor. This explains why they were granted an alternate immortality. It is a common belief that one would live among the gods, while the other was among the dead. The figure of Tyndareus may have entered their tradition to explain their archaic name "Tindaridai" in Spartan inscriptions, or "Tyndaridai" in literature, in turn occasioning incompatible accounts of