Some of those assumed illustrations of American palæolithic art cannot be accepted. One implement, for example, from the Californian gravel-drift, is a polished stone plummet perforated at one end, and not only modern in character, but as a genuine discovery in the gold-bearing gravels, tending to discredit the palæolithic origin assigned to ruder implements found under similar circumstances. But the most startling examples of this class are of minor importance when compared with reported discoveries of human remains in the Californian drift. In 1857, Dr. C. F. Winslow produced a fragment of a human skull found eighteen feet below the surface in the “pay drift” at Table Mountain, associated with remains of the mastodon and fossil elephant. From beds underlying the lava and volcanic tufa of California, from time to time other evidences of the assumed ancient presence of man and traces of his art are produced. But the manifestly recent character of some of the latter prove the disturbance of these deposits by subsequent influences. In 1869 Professor J. D. Whitney exhibited, at the Chicago meeting of the American Association for the Advancement of Science, a complete human skull, recovered at a depth of 130 feet in the auriferous gravel of Calaveras County, California, underlying five successive beds of lava and volcanic tufa, and vouched for its geological antiquity. The gravel which adhered to the relic found imbedded in it is referred by him to the Pliocene age; and Dr. J. W. Foster remarks of it, in his _Prehistoric Races of the United States_: “This skull, admitting its authenticity, carries back the advent of man to the Pliocene epoch, and is therefore older than the stone implements of the drift-gravel of Abbeville and Amiens, or the relics furnished by the cave-dirt of Belgium and France.” In reality, however, the authenticity of the skull as a pliocene relic cannot be admitted. Like that of Guadaloupe, those found by Dr. Lund in the Brazil caves, and other fossil skulls of the American continent, it proved, according to the trustworthy report of Dr. Wyman, to be of the ordinary Indian type; though to some minds that only confirms the genuineness of the discovery. A human skull recovered from the delta of the Mississippi at New Orleans, and estimated by Dr. Dowler—on what, “to avoid all cavil,” he claimed to be extremely moderate assumptions,—as not less than 57,000 years old, is grouped with others found by Dr. Lund in one of the Brazil caves, at Logoa Santa, and thus commented on: “Numerous species of animals have been blotted from creation since American humanity’s first appearance. The form of these crania, moreover, proves that the general type of races inhabiting America at that inconceivably remote era was the same which prevailed at the Columbian discovery”;[42] and so the authors of _Types of Mankind_ arrived at the conclusion that with such evidence of the native American type having occupied the continent in geological times, before the formation of the Mississippi alluvia, science may spare itself the trouble of looking elsewhere for the origin of the American race! The high authority of Professor Agassiz was adduced at the time in support of this and other equally crude assumptions; but they have ceased to receive the countenance of men of science.