Cushing's work was devoted, however, to the investigation of remains analogous to, if not identical with, the Casa Grande, his report forms a valuable contribution to the literature of this subject, and although not everyone can accept the broad inferences and generalizations drawn by Mr. Cushing—of which he was able, unfortunately, to present only a mere statement—the report should be consulted by every student of southwestern archeology.

The latest contribution to the literature of the Casa Grande is a report by Dr. J. Walter Fewkes,8 also of the Hemenway expedition, under the title "On the present condition of a ruin in Arizona called Casa Grande." Two magnificent illustrations are presented, engravings from photographs, showing general views of the ruin, as well as a number of views depicting details, and the ground plan presented at the end of the report is the best so far published. It is unfortunate that this author was not able to give more time to the study of the ruin; yet his report is a valuable contribution to our knowledge concerning the Casa Grande.

DESCRIPTION.

THE CASA GRANDE GROUP.

The Casa Grande has been variously placed at from 2 leagues to 2 miles south of Gila river. The writer has never traversed the distance from the ruin to the river, but the ruin is about a mile from Walker ranch, which is well known in that neighborhood, and about half a mile from the river. This question, however, is not of much importance, as the ruin is easily found by anyone looking for it, being located directly on one of the stage routes from Casa Grande station, on the Southern Pacific railroad, to Florence, Arizona, and about 9 miles below, or west of, the latter place.

The name Casa Grande has been usually applied to a single structure standing near the southwestern corner of a large area covered by mounds and other débris, but some writers have applied it to the southwestern portion of the area and even to the whole area. The latter seems the proper application of the term, but to avoid confusion, where both the settlement as a whole and that portion which has formed the theme of so many writers are referred to, the settlement will be designated as the Casa Grande group, and the single structure with standing walls as the Casa Grande ruin.

Probably no two investigators would assign the same limits to the area covered by the group, as the margins of this area merge imperceptibly into the surrounding country. The accompanying map (plate LI) shows this area as interpreted by the writer. The surface covered by well defined remains, as there shown, extends about 1,800 feet north and south and 1,500 feet east and west, or a total area of about 65 acres.

PLATE LI

MAP OF CASA GRANDE GROUP

The Casa Grande ruin, as the term is here used, occupies a position near the southwestern corner of the group, and it will be noticed that its size is insignificant as compared with that of the entire group, or even with the large structure in the north-central part of it. The division of the group into northern and southern portions, which has been made by some writers, is clearly shown on the map; but this division is more apparent than real. The contour interval on the map is one foot—a sufficiently small interval to show the surface configuration closely and to bring out some of its peculiarities. Depressions are shown by dotted contours. It will be noticed that while most of the mounds which mark the sites of former structures rise but 10 feet or less above the surrounding level, the profiles vary considerably, some being much more smoothed off and rounded than others, the former being shown on the map by even, "flowing" contours, while the latter are more irregular; and it will be further noticed that the irregularity reaches its maximum in the vicinity of the Casa Grande ruin proper, where the ground surface was more recently formed, from the fall of walls that were standing within the historical period.

External appearance is a very unsafe criterion of age, although in some cases, like the present, it affords a fair basis for hypothesis as to comparative age; but even in this case, where the various portions of the group have presumably been affected alike by climatic and other influences, such hypothesis, while perhaps interesting, must be used with the greatest caution. Within a few miles of this place the writer has seen the remains of a modern adobe house whose maximum age could not exceed a decade or two, yet which presented an appearance of antiquity quite as great as that of the wall remains east and southeast of the Casa Grande ruin.

The application of the hypothesis to the map brings out some interesting results. In the first place, it may be seen that in the lowest mounds, such as those in the northwestern corner of the sheet, on the southern margin, and southwest of the well-marked mound on the eastern margin, the contours are more flowing and the slopes more gentle than in others. This suggests that these smoothed mounds are older than the others, and, further, that their present height is not so great as their former height; and again, under this hypothesis, it suggests that the remains do not belong to one period, but that the interval which elapsed between the abandonment of the structures whose sites are marked by the low mounds and the most recent abandonment was long. In other words, this group, under the hypothesis, affords another illustration of a fact constantly impressed on the student of southwestern village remains, that each village site marks but an epoch in the history of the tribe occupying it—a period during which there was constant, incessant change, new bands or minor divisions of the tribe appearing on the scene, other divisions leaving the parent village for other sites, and the ebb and flow continuing until at some period in its history the population of a village sometimes became so reduced that the remainder, as a matter of precaution, or for some trifling reason, abandoned it en masse. This phase of pueblo life, more prominent in the olden days than at present, but still extant, has not received the prominence it deserves in the study of southwestern remains. Its effects can be seen in almost every ruin; not all the villages of a group, nor even all the parts of a village, were inhabited at the same time, and estimates of population based on the number of ruins within a given region, and even those based on the size of a given ruin, must be materially revised. As this subject has been elsewhere9 discussed, it can be dismissed here with the statement that the Casa Grande group seems to have formed no exception to the general rule, but that its population changed from time to time, and that the extent of the remains is no criterion of the former population.

It will be noticed that in some of the mounds, noticeably those in the immediate vicinity of the Casa Grande ruin, the surface is very irregular. In this instance the irregularity indicates a recent formation of surface; for at this point many walls now marked only by mounds were standing within the historical period. External contour is of course a product of erosion, yet similarity of contour does not necessarily indicate either equal