In the original description of _Putorius audax_ (here regarded as inseparable from _Putorius arcticus_ Merriam) Barrett-Hamilton erroneously designated the type locality as "Discovery Bay, North Greenland" whereas he should have written Grinnell Land [= Ellesmere Island of modern terminology] in place of Greenland. As reference to Nares (1877 and 1878) will readily reveal, Discovery Bay is near 65° W and 81° 40´ N, across Robeson Channel, to the west, from Greenland. The label on the type specimen and the specimen register in the British Museum of Natural History each designates the locality for this specimen, the type of _audax_, as Discovery Bay without mention of Greenland. The published accounts of Feilden (1878) and Nares (1877 and 1878) state that specimens of ermine were obtained at Discovery Bay. Probably H. C. Hart is the collector of the specimen; he was the naturalist attached to H. M. S. Discovery which wintered at Discovery Bay while H. W. Feilden was the naturalist attached to H. M. S. Alert which wintered a few miles southeast of Cape Sheridan, also on the eastern coast of Ellesmere Island.
It is true that from these ships a trip was made into Greenland and an ermine (only one individual it seems) was obtained there, but this individual was the type specimen of _Mustela erminea polaris_, in the account of which race something of the history of this specimen is given.
With the material available--and it is not entirely adequate--I can detect no features by which animals from the type locality of _audax_ can be distinguished from typical _arctica_ which latter name has priority.
Intergradation with _richardsonii_ probably occurs completely across the continent. Intergrades here referred to _arctica_ include those from Fort Goodhope. The one defective specimen from Lake Lebarge, Yukon, is not certainly identified as _arctica_ and how far west of Teslin Lake the boundary-line between _arctica_ and _richardsonii_ should be drawn remains to be ascertained. The one specimen available from Hinchenbrook Island, no. 912 Mus. Vert. Zoöl., an adult female, is doubtfully referred to _arctica_ because the damaged tympanic bullae appear to be no larger than in _alascensis_, and the size of the skull is more as in _alascensis_ although intermediate between that race and _arctica_. Shape of the skull is more as in _arctica_. Possibly more nearly adequate material would show the existence on Hinchenbrook Island of an insular race differing in about the same degree from _arctica_ of the mainland as does the insular _kadiacensis_. Nevertheless, the males from farther south at Cape Yakataga are in all respects _arctica_ and this argues against near relationship to _alascensis_ of the animal on Hinchenbrook Island. The three animals seen from Yakutat Bay are so young as not to display clearly the cranial characters of the subspecies but the extension of the color of the underparts onto the underside of the tail in them and also in the skin without corresponding skull from Glacier Bay, Alaska, is as in _arctica_, the race to which they are referred, and gives substantial basis for showing the geographic range of _arctica_ as extending this far south along the Pacific Coast.