We have resolved a nomenclatural problem discovered during research on the northern fur seal that concerns the correct generic name for this taxon and for fur seals of the Southern Hemisphere. The unfortunate practice by some 19th-century authors to use names in their Latinized form but to date them from their first appearance as French common names led to the use of Arctocepbalus for southern fur seals when the name correctly applies to the northern fur seal, known today as Callorbinus ursinus. However, Arctocepbalus and Callorbinus are antedated by Otoes G. Fischer, 1817, which is the earliest available generic name for the fur seal of the northern Pacific. The earliest available generic name for southern fur seals is Halarctus Gill, 1866. To avoid the confusion that would result from replacing the currently used generic names with those required by strict adherence to the Principle of Priority, we have petitioned the International Commission on Zoological Nomenclature to preserve Arctocepbalus and Callorbinus for the southern and northern fur seals, respectively.