It was more than fifteen miles to the next water-hole. This may have been the second or even the third day that the coyotes had been worrying her. I frightened them away, but had not gone half a mile when I saw them circling back again. I do not know the end of the story, but as I walked on I wished that this mother antelope might have possessed the special development of the pronghorn in the desert regions--the ability to do without water for days at a time. The food of the pronghorn is sage, greasewood, sometimes cactus, and, on the desert, broomrape. I do not recall ever seeing him eat grass. In the extremely arid regions of the Southwest the local flocks, in common with mountain sheep and other animals of the desert, have developed the habit of doing without water for days--sometimes for a period of two weeks or longer have no other moisture than that furnished by the plants eaten. When the young antelope are about three weeks old they appear to have full use of their legs and usually follow the mother in feedings and fights. At this time numbers of mothers and youngsters collect and run together. They are thus enabled to give mutual aid and to withstand coyotes and other enemies better. Sometimes under dangerous conditions the young are left behind while some of the mothers go for water, and on their return the remaining ones go. Just why this mutual aid is not practised while the young are almost helpless is not clear. In early autumn all ages and sexes unite and commonly run together, often in large flocks, throughout the winter. The youngsters often play together. Frequently one of the males is the lively leader of twenty or thirty. At other times the old antelopes play, go through a series of marches and countermarches. They race back and forth and over short circles. When thus engaged they commonly have sentinels posted on the outskirts. Most other animals appear to forget possible enemies while playing, but the nervous antelope, with big open spaces round it, appears never to be quite in repose. Depending upon speed rather than upon stealth, fighting ability, or concealment, as a means of escaping enemies, and living in the plains with a magnificence of unobstructed distances, it has learned to be watchful, to use sentinels, and to flee even when danger is afar. Usually when the antelope lies down it selects a spot well away from any ravine, bluff, willow clump, or sagebrush thicket that could conceal an enemy or that would enable an enemy to approach it closely unseen. Under most conditions the female appears to be the acknowledged leader. In the majority of instances in which I have watched moving flocks of antelope--fleeing small numbers or a number of alarmed antelope preparing to move--it was under female leadership.