Siberian beaver

The intense, for the Siberian beaver leathery, odor of castoreum is caused largely by phenolic compounds (e.g., 4-alkylphenols and catechol derivatives [256]), which beavers take in with their food and excrete into their abdominal pouch. Castoreum was used mainly in fine fragrances for its characteristic, long-lasting odor, particularly for delicate leather nuances. FCT 1973 (11) p. 1061 [8023-83-4], [92704-04-6], [92704-05-7]. 

Beavers are large pale brown to chestnut-brown rodents. The Canadian beaver inhabits lakes and rivers of Canada and northern United States, while the Siberian beaver is found in Europe and Siberia. Castoreum is the secretion accumulated in glands located near the pubis (between anus and sex organs) of these animals. These scent glands with their secretion (castoreum) are collected and dried, from which extracts (absolute, tincture etc.) are prepared by solvent extraction. Canadian castoreum is considered superior in quality to the Siberian castoreum. ... 

Common/vernacular names Secretion of Canadian beaver (C. canadensis) and Siberian or European beaver (C. fiber). 

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