_Significance of structural plan._--The designation of the curious orifice of the sipapuh as “the place from which the people emerged” in connection with the peculiar arrangement of the kiva interior with its change of floor level, suggested to the author that these features might be regarded as typifying the four worlds of the genesis myth that has exercised such an influence on Tusayan customs; but no clear data on this subject were obtained by the writer, nor has Mr. Stephen, who is specially well equipped for such investigations, discovered that a definite conception exists concerning the significance of the structural plan of the kiva. Still, from many suggestive allusions made by the various kiva chiefs and others, he also has been led to infer that it typifies the four “houses,” or stages, described in their creation myths. The sipapuh, with its cavity beneath the floor, is certainly regarded as indicating the place of beginning, the lowest house under the earth, the abode of Myuingwa, the Creator; the main or lower floor represents the second stage; and the elevated section of the floor is made to denote the third stage, where animals were created. Mr. Stephen observed, at the New Year festivals, that animal fetiches were set in groups upon this platform. It is also to be noted that the ladder leading to the surface is invariably made of pine, and always rests upon the platform, never upon the lower floor, and in their traditional genesis it is stated that the people climbed up from the third house (stage) by a ladder of pine, and through such an opening as the kiva hatchway; only most of the stories indicate that the opening was round. The outer air is the fourth world, or that now occupied. There are occasional references in the Tusayan traditions to circular kivas, but these are so confused with fantastic accounts of early mythic structures that their literal rendition would serve no useful purpose in the present discussion. _Typical measurements._--The following list is a record of a number of measurements of Tusayan kivas collected by Mr. Stephen. The wide difference between the end measurements of the same kiva are usually due to the interior offsets that have been noticed on the plans, but the differences in the lengths of the sides are due to irregularities of the site. The latter differences are not so marked as the former.