In this classification no mention has been made of the cliff and cave ruins. These structures belong partly to class III, villages on defensive sites, and partly to a subclass which pertained to a certain extent to all the others. In the early stages of pueblo architecture the people lived directly on the laud they tilled. Later the villages were located on low foothills overlooking the land, but in this stage some of the villages had already attained considerable size and the lands overlooked by them were not sufficient for their needs. As a consequence some of the inhabitants had to work fields at a distance from the home village, and as a matter of convenience small temporary shelters were erected near by. In a still later stage, when the villages were removed to higher and more easily defended sites, the number of farming shelters must have largely increased, as suitable sites which also commanded large areas of good land could not often be found. At a still later stage, when the inhabitants of a number of small villages combined to form one large one, this difficulty was increased still more, and it is probable that in this stage the construction of outlying farming settlements attained its maximum development. Often whole villages of considerable size, sometimes many miles from the home pueblo, were nothing more than farming shelters. These villages, like the single-room shelters, were occupied only during the farming season; in the winter the inhabitants abandoned them completely and retired to the home village. Some farming villages, such as those described above, are still in use among the pueblos. The little village of Moen-Kapi, attached to Oraibi, but 75 miles distant from it, is an example. There are also no fewer than three villages in the Zuni country of the same class. Nutria, Pescado, and Ojo Caliente are summer villages of the Zuni, although distant from that pueblo from 15 to 25 miles. It is significant that none of these subordinate villages possess a kiva. It is believed that the cliff ruins and cavate lodges, which are merely variants of each other due to geological conditions, were simply farming shelters of another type, produced by a certain topographic environment.