The prickly pear, that ugly, fleshy little cactus, with its sudden summer glories of crimson and golden blossoms, fulfils a strange purpose in the animal economy of the prairies. In itself it appears to be one of the veriest outcasts among vegetables, execrated by man and refused as food by beast. Yet if it were not for this plant the herds of prairie antelope would have fared badly enough, for the antelope, whenever they found themselves in straits from wolves or from dogs, made straight for the prickly pear patches and belts, and there, standing right out on the barren, open plain, defied their swift but tender-footed pursuers to come near them. For the small, thick pads of the cactus, though they lie so flat and insignificantly upon the ground, are studded with tufts of strong, fierce spines, and woe to the wolf or the dog that treads upon them. The antelope's hoofs, however, are proof against the spines, and one leap across such a belt suffices to place the horned folk in safety. These patches and belts, then, so trivial to the eye, and in some places almost invisible to the cursory glance, are in reality Towers of Refuge to the great edible division of the wild prairie nations, and as impassable to the eaters as was that girdle of fire and steel which Von Moltke buckled so closely round the city of the Napoleons. But here we are approaching Denver. The cottonwood has mustered into clusters, a prototype of the future of these now scattered ranches. Dotted about here and there in suitable corners, on river bank or under sheltering bluff, single trees are growing side by side with single stockyards or single cow-boys' huts, but every now and again, where nature offers them a good site for a colony, the trees congregate, select lots, and permanently locate. It is not very different after all, with human beings. Nature here is undoubtedly tempting, and Denver itself must surely be one of the most beautiful towns in the States. Through great reaches of splendid farm-land, with water in abundance and the cottonwood and willow growing thickly, we pass to our destination as the twilight settles on the country. A whole day has again been spent in the train! We had awaked in the morning to see from the car windows the people of Nebraska going out to their day's work in the fields, and here in the evening we sit and watch the Colorado folk coming home to their rest after the day's work is over. Truly this steam is a Latter-Day apocalypse and this America a land of magnificent distances.