ILLUSTRATIONS. 



Facing- puge. 



Plate I. Map of Alaska Frontispief-e 



II. Fig. 1. — Summit of White Pass. 



Fig. 2. — Canadian police station at Caribou Crossing 10 



III. Fig. 1. — Cliffs on east side of Lake Lebarge. 



Fig. 2.— Yukon River 50 miles below Fort 8elkirk(^ 12 



IV. Fig. 1. — Nests of red squirrels in spruce thicket. 



Fig. 2. — Burrows made by red squirrels in loose scales stripped 



from spruce cones 26 



A^. Skulls of Scivrus vancouverensis, Sciunis luidsonicus pelulans, Xeo- 



tonia cinerca drummondi, and Xeoloma saxamans 34 



YI. Skulls of Lutreola vison energumenos, Lutreola v. ingens, Fiber ziheth- 



icus, and Fiber sjyatulatus 42 



YII. Skulls of Mustela americana bnnnaliti, Musfela americana artunsn, 



and MuMela americana ''. 44 



6 



