The owner of cattle on the open range must be constantly on his guard against losses by theft. Usually the thief is a dishonest neighbor or one of his own cowboys who becomes thrifty at his employer's expense. Many a herd of cattle was begun without a single cow, but was started by branding surreptitiously other people's property. It is not an easy matter to detect such a thief or to convict on evidence when he is arrested and brought to trial. A cattle thief seldom works alone, but associates himself with others of his kind who will perjure themselves to swear each other clear. The cow ponies that are used in range work are small but active and possessed of great power of endurance. They are the descendants of the horses that were brought into Mexico by the Spaniards, some of which escaped into the wilderness and their increase became the wild horses of the plains. They are known by the various names of mustang, bronco and cayuse according to the local vernacular of the country in which they roam. They are wild and hard to conquer and are sometimes never fully broken even under the severest treatment. Bucking and pitching are their peculiar tricks for throwing a rider and such an experience invariably ends in discomfort if not discomfiture, for if the rider is not unhorsed he at least receives a severe shaking up in the saddle. The native cattle, like the horses, are small and wild, but are hardy and make good rustlers. The native stock has been greatly improved in recent years by cross breeding with thoroughbred Durham and Hereford bulls. Grade cattle are better suited for the open range than are pure bred animals, which are more tender and fare better in fenced pastures. By cross breeding the quality of range cattle has steadily improved until the scrub element has been almost bred out. As a breeding ground Arizona is unsurpassed, but for maturing beef cattle the northern country is preferable. Thousands of young cattle are shipped out annually to stock the ranges of Wyoming and Montana and to fill the feed lots of Kansas, Missouri and other feeding states. A dash of native blood in range cattle is desirable as it enables them to endure hardships without injury and find subsistence in seasons of drought and scant forage. The general round-up occurs in the fall, just after the summer rains, when there is plenty of grass and the horses and cattle are in good condition. The ranchmen of a neighborhood meet at an appointed time and place and organize for systematic work. A captain is chosen who is in command of the round-up and must be obeyed. Each cowboy has his own string of horses, but all of the horses of the round-up not in use are turned out to graze and herd together. A mess wagon and team of horses in charge of a driver, who is also the cook, hauls the outfit of pots, provisions and bedding.