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
Shadow and Substance Shadow and Substance "Shadow and Substance "is an award-winning four-act play written in 1937 by Paul Vincent Carroll. In 1938 it won the New York Drama Critics' Circle award for best foreign play. First published by Samuel French in 1944. Set in Ireland, the play has a cast of six men and four women. According to George Jean Nathan "deals with the Catholic Church in Ireland. Its theme lies in the ramifications of faith as practiced by the Church's various constituents…faith that, for all its sincerity, has drifted from its deepest moorings, and the manner in which a true, steadfast,