ception of one side of one inferior maxillary. This was well preserved, and stained a deep green color. Not understanding the import of this, the laborers missed finding a copper implement of some kind. No other remains were found in the vicinity.
Plan II.
Plan III is a singular group of mounds 3 miles from Spring Hill post-office, Whiteside County, Illinois. The bluffs along Rock River are covered with mounds. This group, however, is on the alluvial bottom, about 30 rods from the river. Though there may be others on the lowlands, yet these are the only ones I found so situated. This group is in a semicircular form, in quite regular lines, as will be seen by a reference to the plan. They are on a plat of ground a little higher than the surrounding level. They are surrounded on three sides by a slough, in earlier times probably communicating with the river, and this may have had some influence in shaping the crescent form of the arrangement. However, being on the ground, the impression cannot be resisted that there was some special design in the grouping.
While most of the mounds were round and of varying size, some of them were long and narrow. The figures inside the circles indicate the dimensions of the larger ones in paces (2½ feet to the pace). Their rel-
