North Pacific Phocidae

p. 459-499 : ill. ; 24 cm.Includes bibliographical references.Nomenclature. The generic name Phoca. Specific names -- Sexual differences in dentition in Phoca vitulina -- Comparison of the Atlantic and Pacific forms of the Phoca vitulina group. Cranial differences. Dental characters. Supernumerary teeth -- The North Pacific Phocidae (with descriptions of new forms)