The molt of the bucks begins in June but takes place chiefly in July, while the animals are somewhere to the north of the Nueltin Lake region. On their return in August they have largely completed their summer transformation in appearance. A buck of August 17 had just a little of the winter fur still clinging to its lower back; and another on August 20 was in similar condition. At this season the white mane is developed only on its lower portion (figs. 9, 10, 12), but by the end of September the white has spread upward over practically the whole neck (fig. 22), and in some cases over the shoulders. In an adult male (No. 1144) of October 16, representing the pelage of the rutting season, the posterior crown is near Tilleul Buff, the anterior crown somewhat browner; sides of head and upper throat between Verona Brown and Buffy Brown; area about and between eyes somewhat darker; triangular area behind nostrils (apex extending halfway to eyes) and lower chin between Mummy Brown and Warm Blackish Brown; tip of snout and chin Cartridge Buff; ears pale creamy white on both surfaces; whole neck and shoulder mantle whitish, washed with Cartridge Buff, and changing gradually to the brownish of the sides of the head; long hairs along median ventral line of the neck tipped with Natal Brown; dorsal area, from shoulders to rump, Prout’s Brown; stripe on lower sides Mummy Brown, separated from dorsal area by an ill-defined lighter stripe, mixed with whitish hairs; top of tail slightly paler than back, the rest white; small rump-patch mostly white; chest Mummy Brown; mid-venter varying from Deep Olive-Buff anteriorly to Cream-Buff posteriorly; posterior venter white; forelegs near Bone Brown; hind legs between Mummy Brown and Olive-Brown, with a pale spot on the inner side of the heel (this spot noticeable also in doe and fawn); hoofs black, bordered above with whitish hairs. The hides of this specimen and of two other adult bucks (No. 1111, September 29, and No. 1132, October 16) were prime. The dark lateral stripe, which shows quite distinctly in summer and fall specimens of both sexes (figs. 7, 8, 10, 21, 22), from fawns (except very young ones) to adults, and which is also a prominent feature in Old World Reindeer (_cf._ Flerov, 1933), has been largely or wholly overlooked in some descriptions of _Rangifer a. arcticus_.