ments are so frequently given on the plates themselves that no confu- 

 sion need occur. Measurements were taken by tape-line in all the more 

 important structures ; but in many of the ordinary ruins, where exact 

 dimeusions were not considered essential, the distances were estimated. 

 It is to be greatly regretted that extreme haste frequently prevented 

 close and accurate work. 



The accompanying map will give the location of all the more important 

 groups of ruins. 



The fragments of information collected in this notice are given with 

 the hope that they may throw a little additional light upon the very 

 interesting problems of ancient American history. 



RUINED VILLAGE ON THE RIO LA PLATA. 

 Plate I. 



The first group of ruins observed is situated on the Rio La Plata, about 

 twenty-five miles above its junction with the San Juan, and three or 

 four miles south of the i^ew Mexican line. It is doubtless the remains 

 of a large irregular village, and stands on a low terrace, some 20 feet 

 above the river-bed, and near the center of a large fertile valley. 



It will be seen, by reference to the plate, which includes only the 

 more important part of the town, that the buildings have been isolated, 

 and, in a measure, independent of each other, differing in this respect 

 from most of the groups of ruins farther south. 



The forms are chiefly rectangles and circles; one or two seem to have 

 been elliptical, while a number have consisted of irregular groui)s or 

 clusters of apartments. All that now remains to mark the site of these 

 ancient structures is the low, rounded heaps and lines of debris, composed 

 of earth, water-worn pebbles, and small fragments of sandstone. The 

 walls of four of the main structures are quite distinctly marked. That of 

 the circle c is still 4 feet high on the outside, and incloses a depression, 

 probably an esUifa, which, in the center, is 2 or 3 feet below the terrace- 

 level. 



North of this, about 300 feet, is a truncated rectangular mound, 9 or 

 10 feet in height and 50 feet in width by 80 in length. On the east end, 

 near one of the angles, is a low, iirojecting pile of debris that may have 

 been a tower. There is nothing whatever to indicate the use of this 

 structure. Its flat top and height give it more the appearance of one 

 of the sacrificial mounds of the Ohio Valley than any other observed in 

 this part of the West. It may have been, however, only a raised foun- 

 dation, designed to support a superstructure of wood or adobe. 



North of this again, and 100 feet distant, is a rectangular inclosure 

 about 60 by 100 feet. It is slightly excavated in the center, and the 

 rounded and irregular wall is from 4 to 6 feet in height. The space be- 

 tween this and the last-mentioned structure is filled in to the depth of 2 

 or 3 feet, and the amount of debris about their bases indicates original 

 walls of considerable height. North of this are scattered a number of 

 inferior ruins, the walls of which are not always distinctly marked. These 

 extend back toward a row of low hills, the remnants of a superior ter- 

 race, on the summits of which a number of artificial depressions were 

 found. Such "dug holes" are generally quite numerous in the vicinity 

 of these ruins, and have doubtless in many cases been made by throw- 

 ing up earthworks for defensive purposes. South of the large circle is 

 a mass of ruins covering some 15,000 square feet, but so much reduced 

 that nothing further could be determined than the fact that it had con- 

 tained a large number of irregular apartments. Next to this is a rect- 



