The pronghorn lives in a home territory. This I think is rarely more than six or eight miles in diameter. If pursued by man, dogs, or wolves it is likely to run in great circles, keeping within the bounds of home territory. Most antelope are not migratory, but in a few localities the flocks make a short migration. For winter they may travel to a more broken locality, one that gives some shelter from the wind and contains spaces off which the wind sweeps the snow. The antelope makes long leaps but not high jumps. I watched an antelope that had been separated from the flock hurrying to rejoin it. In its way was a line of willows along the dry, shallow water channel. This willow stretch was not wide nor high. A deer would have leaped it without the slightest hesitation. The antelope went far round and jumped wide gullies, but made no attempt to leap this one low line of willows. Being a plains animal, knowing but little of cliffs and timber, it has not learned high jumping. For ages the antelope was thickly scattered over the Great Plains and the small parks of the West, Northwest, and Southwest. Fifty years ago they were numbered by millions. The present antelope population numbers not more than 15,000. Howard Eaton tells me that years ago he sometimes saw several thousand in a single day. Once when a boy I saw at least a thousand in a North Park, Colorado, flock. A few are now protected in the national parks and in private antelope reserves. But they are verging well toward extermination. Rarely does the antelope thrive in captivity. Apparently the food ordinarily fed it in captivity does not agree with it. Mature antelope are marked with what may be called revealing colours, which advertise their presence and make them easily visible at long distances: rich tan to grayish brown on the back and sides, with clean white buttocks and sides of face and belly; the throat faintly striped with white and brown; and a touch of near-black on the head. The antelope’s colour is so distinctive and stands out so well against most backgrounds that it may be classed as an animal with revealing coloration. Two white rump patches flare up during excitement; the crowded and bristling hairs may be seen at surprisingly long distances. Possibly these hairs are also under conscious control. At any rate, let one or a number on a ridge see an approaching enemy and these white patches stand out, and the next adjacent flock, even though two or three miles away, will see the sign--or signal--and also take alarm. Though the antelope does not do any wireless wigwagging, the sudden flare of white buttocks is revealing. Depending chiefly on speed in escaping his enemies, the antelope has also the added advantage of being able to detect an enemy while he is still afar. The plains where he lives enable him to see objects miles away, and his eyes being of telescopic nature ofttimes enable him to determine whether a distant moving object is friend or foe.