1. The earliest form of pueblo house is doubtful. As a rule, in most localities the earliest forms are already well advanced. As it is now known that the ancient pueblo region was not inhabited by a vast number of people, but by a comparatively small number of little bands, each in constant though slow movement, this condition is what we would expect to find. It is probable that the earliest settlements consisted of single houses or small clusters located in valleys convenient to areas of cultivable land and on streams or near water.

2. The next step gives us villages, generally of small size, located on the foothills of mesas and overlooking large areas of good land which were doubtless under cultivation. This class comprises more examples perhaps than any other, and many of them come well within the historic period, such as six of the seven villages of Tusayan at the time of the Spanish conquest in 1540, all of the Cibolan villages of the same date, and some of the Rio Grande pueblos of that time.

3. In some localities, though not in all, the small villages were at a later period moved to higher and more inaccessible sites. This change has taken place in Tusayan within the historic period, and in fact was

not wholly completed even fifty years ago. The pueblo of Acoma was in this stage at the time of the conquest, and has remained so to the present day. As a rule each of the small villages preserved its independence, but in some cases they combined together to occupy together a high defensive site. Such combination is, however, unusual.

4. The final stage in the development of pueblo architecture is the large, many-storied, or beehive village, located generally in the midst of broad valleys, depending on its size and population for defense, and usually adjacent to some stream. In this class of structure the defensive motive, in so far as it affected the choosing of the site, entirely disappears. The largest existing pueblo, Zuñi, made this step early in the eighteenth century; the next largest, Taos, was probably in this stage in 1540, and has remained so since. In some cases ruins on foothill sites (2) have merged directly into many-storied pueblos on open sites (4), without passing through an intermediate stage.

There is another step in the process of development which is now being taken by many pueblos, which, although an advance from the industrial point of view, is to the student of architecture degeneration. This consists of a return to single houses located in the valleys and on the bottom lands wherever convenience to the fields under cultivation required. This movement is hardly twenty years old, but is proceeding at a steadily accelerating pace, and its ultimate result is the complete destruction of pueblo architecture. Whatever we wish to know of this phase of Indian culture must be learned now, for two generations hence probably nothing will remain of it.

This hasty sketch will illustrate some of the difficulties that lie in the way of a complete classification of the ruins of the pueblo country. It is impossible to arrange them in chronologic sequence, because they are the product of different tribes who at different times came under the influence of analogous causes, and results were produced which are similar in themselves but different in time. It is believed, however, that the classification suggested exhibits a cultural sequence and probably within each tribe a chronologic order.

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 Zuñi country of the same class. Nutria, Pescado, and Ojo Caliente are summer villages of the Zuñi, 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.