The bighorn resembles the wapiti in colour, although it is of a lighter brown, especially in winter. It is clothed with wool beneath the stiff outer coat of hair, and is a true sheep, but larger than any domesticated variety of _Ovis_. The rams attain a height of at least 3 feet 6 inches at the shoulder, and weigh some 300 or 400 pounds. Both sexes are provided with horns, but those of the male are much the larger, and in the finest examples attain a length of 30 inches, measured along the outer curve, and a circumference at the base of 15 or 16 inches. The most magnificent head ever obtained, so far as the writer has been able to learn, is that of a ram shot in the Selkirk Mountains, the horns of which are 521/2 inches in length, measured along the outer curve, and 181/2 inches in circumference at the base. These immense horns are used, as in the case of the domestic ram, in fighting, but the widely current statement in reference to the animals alighting on them when jumping from precipices is entirely mythical. The bighorn is a fearless and skilful mountaineer, and will climb or descend precipices by bounding from ledge to ledge where the most reckless hunter dares not follow. Its ability to find a sure footing on even smoothly glaciated rocks is due to the peculiar structure of the feet, which have a rubber-like pad beneath the sharp-pointed and sharp-edged hoofs. _The Mazama or Mountain-Goat._--The companion of the bighorn on the lofty mountains, but even more thoroughly a mountaineer, is the so-called mountain-goat, _Aplocerus montanus_, which, in spite of its long hair, short curved horns, sturdy legs, bearded chin, and general goat-like appearance, and more than the goat's ability to climb, is in reality more nearly related to the antelope than it is to the sheep. This alpine antelope, unlike its cousin of the plains, is only at home on dizzy heights, and summer and winter alike lives at timber-line on the mountains or in the alpine gardens adjacent to perpetual snow. One of the earliest generic names under which it is assumed this alpine antelope was included, namely, _Mazama_, although rejected by naturalists, has recently been revived and adopted by an enthusiastic mountaineering club in Portland, Oregon, as their name, and is likely to become widely known. Among the hunters and the inhabitants generally of the region where the animal under consideration lives it is termed the mountain-goat, and no protest from naturalists, however well founded, is likely to bring about a change in this connection.