No gnawed bones nor any coprolites were found by Schmerling. He therefore inferred that the caverns of the province of Liege had not been the dens of wild beasts, but that their organic and inorganic contents had been swept into them by streams communicating with the surface of the country. The bones, he suggested, may often have been rolled in the beds of such streams before they reached their underground destination. To the same agency the introduction of many land-shells dispersed through the cave-mud was ascribed, such as Helix nemoralis, H. lapicida, H. pomatia, and others of living species. Mingled with such shells, in some rare instances, the bones of freshwater fish, and of a snake (Coluber), as well as of several birds, were detected. The occurrence here and there of bones in a very perfect state, or of several bones belonging to the same skeleton in natural juxtaposition, and having all their most delicate apophyses uninjured, while many accompanying bones in the same breccia were rolled, broken, or decayed, was accounted for by supposing that portions of carcasses were sometimes floated in during floods while still clothed with their flesh. No example was discovered of an entire skeleton, not even of one of the smaller mammalia, the bones of which are usually the least injured. The incompleteness of each skeleton was especially ascertained in regard to the human subjects, Dr. Schmerling being careful, whenever a fragment of such presented itself, to explore the cavern himself, and see whether any other bones of the same skeleton could be found. In the Engis cavern, distant about eight miles to the south-west of Liege, on the left bank of the Meuse, the remains of at least three human individuals were disinterred. The skull of one of these, that of a young person, was embedded by the side of a mammoth's tooth. It was entire but so fragile, that nearly all of it fell to pieces during its extraction. Another skull, that of an adult individual, and the only one preserved by Dr. Schmerling in a sufficient state of integrity to enable the anatomist to speculate on the race to which it belonged, was buried 5 feet deep in a breccia, in which the tooth of a rhinoceros, several bones of a horse, and some of the reindeer, together with some ruminants, occurred. This skull, now in the museum of the University of Liege, is figured in Chapter 5 (Figure 2), where further observations will be offered on its anatomical character, after a fuller account of the contents of the Liege caverns has been laid before the reader.