There is no occasion to speak here of the many remains of neolithic man that have been exhumed. Sparse in the early part of the age of polished stone weapons, they gradually became numerous, and merged into the human remains of late prehistoric times. The American continent is not without its relics of ancient man, the most famous of which is the Calaveras skull, found in 1886 in the auriferous gravels of Calaveras County, California, at an extraordinary depth. The miners, in excavating a shaft, passed through several layers of lava and gravel, forming a total thickness of seventy-nine feet of lava and a considerable thickness of gravel, making nearly one hundred and thirty feet in all. At this depth a skull was found imbedded in the gravel, which, if authentic, must have been overflowed by several successive thick outpours of lava in the ancient volcanic era of that region. As its authenticity is, however, still a matter of controversy, nothing further need here be said about it. Leaving these evidences of human antiquity, we come to the most remarkable and significant of all the known relics of man, if indeed it is man, for it seems to many a link between man and the ape,--not yet human, while no longer simian. This is the fossil find made by Dr. Eugene Dubois in 1891 on the banks of the Bengawan River, Java, and named by him _Pithecanthropus erectus_, he maintaining that it represents a new genus of upright animals, or even a new family. The remains found by him consisted of the upper part of a skull, a molar tooth, and a femur, possibly not belonging to a single individual, as they were somewhat separated. These were exhumed from a stratum of volcanic tufa, claimed to be of Tertiary age, but perhaps Quaternary, and lay at a depth of some forty feet beneath the surface. The femur very closely resembles that of a human being of average size, and its shape, articulating surface, and other characters show clearly that the animal stood habitually erect. The principal significance lies in the tooth and the cranium. The former is like that of the chimpanzee in shape, but less rugose on its grinding surface. It seems to lie between the ape and the human type of dentition. The cranium has a low, depressed arch, with a very narrow frontal region and highly developed superciliary ridges. The cranial capacity was apparently about one thousand, that of man being from thirteen hundred to fourteen hundred. It is therefore said to be "the lowest human cranium yet described, very nearly as much below the Neanderthal as that is below the normal European."