Their nests are set amid the rocks, and are quite bulky, the walls composed of grasses and the lining consisting of soft feathers. In order to procure the grasses required, they must descend at least to the belt of scant vegetation just below the region of bare rocks and boulders. Where they get the downy feathers for the carpet of their nurseries I have not been able to ascertain. No nest has yet been discovered below an elevation of 12,000 feet. Our little bird may, indeed, be called a "haunter of the sky." The height of the breeding season is in the latter part of July. The broods having left the nests, old and young gather in small flocks and range over the peaks and ridges, feeding on the insects to be found on the fields of snow. No less interesting are the habits of these birds in winter. In October and November most of them descend only to the timber line, where they remain throughout the winter, save as they are driven down into the denser forests by the fierce tempests of this arctic region. What feathered Vikings they are! They do not even make for themselves snow huts for protection from the winter storms. However, a few descend almost to the base of the foothills, while others--perhaps the less hardy--seek a blander climate in the northern part of Mexico. There are in North America four other species of the genus Leucosticte; the Aleutian, whose habitat is the Aleutian and Prybilof islands and east as far as the island of Kadiak; the gray-crowned, which breeds in British America near the Rocky Mountains, comes to Colorado in winter, and has been taken as far east as western Iowa; the Hepburn, dwelling chiefly in the mountain ranges of the Pacific coast, breeding mostly in the far North, and in winter coming as far south and east as Nevada and Colorado; and, lastly, the black leucosticte, which winters in the central latitudes in the Rocky Mountains and whose summer range and breeding home is unknown to men of science. HAPPENINGS BY THE WAY If one were to keep on writing monographs of all our interesting avian species, the books that would result would make a good-sized library. The few examples that have been given will illustrate what can be done in this direction with the help of the field glass and the handbook. A few chapters will now be given on what might be called "odds and ends of bird life," and these are written not only for the information they may impart, but also for the purpose of showing how many interesting facts can be gathered along the way by the method of bird study commended in our opening chapter.