The case is simple. During the past winter, while the Antelope were gone southward, the Canadian Pacific Railway Company had fenced its track. In spring the migrants, returning, found themselves cut off from their summer feeding-grounds by those impassable barb-wires, and so were gathered against the barrier. One band of 8, at a stopping place, ran off when they saw passengers alighting, but at half a mile they turned, and again came up against the fence, showing how strong is the northward impulse. Unless they learn some way of mastering the difficulty, it means extermination for the Antelope of the north Saskatchewan. From Calgary we went by train to Edmonton. This is the point of leaving the railway, the beginning of hard travel, and here we waited a few days to gather together our various shipments of food and equipment, and to await notice that the river was open. In the north the grand event of the year is the opening of the rivers. The day when the ice goes out is the official first day of spring, the beginning of the season; and is eagerly looked for, as every day's delay means serious loss to the traders, whose men are idle, but drawing pay as though at work. On May 11, having learned that the Athabaska was open, we left Edmonton in a livery rig, and drove 94 miles northward though a most promising, half-settled country, and late the next day arrived at Athabaska Landing, on the great east tributary of the Mackenzie, whose waters were to bear us onward for so many weeks. Athabaska Landing is a typical frontier town. These are hard words, but justified. We put up at the principal hotel; the other lodgers told me it was considered the worst hotel in the world. I thought I knew of two worse, but next morning accepted the prevailing view. Our canoe and provisions arrived, but the great convoy of scows that were to take the annual supplies of trade stuff for the far north was not ready, and we needed the help and guidance of its men, so must needs wait for four days. This gave us the opportunity to study the local natural history and do a little collecting, the results of which appear later. The great size of the timber here impressed me. I measured a typical black poplar (P. balsamifera), 100 feet to the top, 8 feet 2 inches in circumference, at 18 inches from the ground, and I saw many thicker, but none taller.