The chief kiva at Walpi, that used by the Snake fraternity, is rectangular and subterranean, while that used by the Flute priests, which is practically a ceremonial room, is a chamber entered by a side doorway. It is suggested that the Snake kiva at Walpi was derived from the circular subterranean kiva of Tokónabi, the former home of the Snake clan in northern Arizona, and that the Flute chamber was developed from the rectangular rooms in the same ruins. The old question, so often considered by Southwestern archeologists, whether the circular subterranean kiva was derived from the rectangular or _vice versa_, seems to the writer to be somewhat modified by the fact that ceremonial rooms of both forms exist side by side in many ancient cliff-dwellings. From circular subterranean kivas in some instances developed square kivas, but the latter are sometimes the direct development of square rooms; the determination of the original form can best result from a study of clans and their migrations.[55] Naturally the questions one asks in regard to these ruins are: Why did the inhabitants build in these cliffs? Who were the ancient inhabitants? When were these dwellings inhabited and deserted? It is commonly believed that the caves were chosen for habitations because they could be better defended than villages in the open. This is a good answer to the first question, so far as it goes, although somewhat imperfect. The ancients chose this region for their homes on account of the constant water supply in the creek and the patches of land in the valley that could be cultivated. This was a desirable place for their farms. Had there been no caves in the cliffs they would probably have built habitations in the open plain below. They may have been harassed by marauders, but it must be borne in mind that their enemies did not come in great numbers at any one time. Defense was not the primary motive that led the sedentary people of this canyon to utilize the caverns for shelter. Again, the inroads of enemies never led to the abandonment of these great cliff-houses, if we can impute valor in any appreciable degree to the inhabitants. Fancy, for instance, the difficulty, or rather improbability, of a number of nomadic warriors great enough to drive out the population of Kitsiel, making their way up Cataract canyon and besieging the pueblo. Such an approach would have been impossible. Marauders might have raided the Kitsiel cornfields, but they could not have dislodged the inhabitants. Even if they had succeeded in capturing one house but little would have been gained, as it was a custom of the Pueblos to keep enough food in store to last more than a year. In this connection the question is pertinent, While hostiles were besieging Kitsiel how could they subsist during any length of time? Only with the utmost difficulty, even with aid of ropes and ladders, can one now gain access to some of these ruins.