OPIXIOXS CONCERNING THE CALAVERAS SKULL. 195 



acceptance ; and finally th€ traces of such a cleft would certainly have been 

 detected by Professor Whitney, his three assistants and several personal 

 friends, all of whom carefully examined the locality with the finder of the 

 skull not long after its discovery became known. I find that many good 

 judges are fully persuaded of the authenticity of the Calaveras skull, and 

 Messrs. Clarence King, O. C. Marsh, F. W. Putnam and W. H. Dall have 

 each assured me of his conviction that this bone was found in place in the 

 gravel beneath the lava.* Dr. Alfred R. Wallace, too, who has seen at 

 least some of the auriferous gravels and table mountains, in speaking both 

 of the implements found and the Calaveras skull, stated that these remains 

 "present all the characteristics of genuine discoveries." f 



Conclusion as to Facts. — The new evidence brought forward in this paper 

 seems to me a considerable contribution to the argument in favor of the 

 authenticity of the skull and amply sufl[icient of itself to prove that man 

 existed during the Auriferous gravel period in California. 



As for the accompanying mammalian remains, I am not aware that their 

 authenticity has ever been questioned, while the Tertiary facies of some of 

 them is freely acknowledged. Since the relics of humanity occur down to the 

 very bottom of the gravels, it seems to me altogether probable that the beasts 

 were contemporaneous with the human beings, for the advent of the last great 

 lava flows and the subsequent glaciation seem the only known events adequate 

 to account for their extinction or expulsion. There is a possibility, however, 

 that the great beasts were all dead before human occupation began, just as 

 to-day implements or human bones might be mingled with the remains of 

 animals already extinct, but still lying at or near the surface. Even on 

 such an hypothesis the remains of Homo sapiens and other animals in the 

 gravels must be referred to the same geological horizon. 



Many naturalists like Mr. Wallace would be little surprised at the dis- 

 covery of paleolithic implements in the Pliocene, for there is considerable 

 evidence that men must have existed in some quarters of the globe thus 

 early. It is the relatively high stage of development indicated by the char- 

 acter of the tools which inclines some students to discredit the discoveries. 

 We seem to be on the horns of a dilemma ; either man reached the neolithic 

 stage in California much earlier than in other parts of the globe, or the 

 paleontologists are wrong in their reference of certain of the mammals to the 

 Pliocene fauna. I seem, however, to see a tertium quid worth suggesting, 

 but to which I am not ready to commit myself finally. In order to explain 

 my trial hypothesis I must make a short digression on the age of the glacial 

 phenomena in California. 



* This statement is made by permission. 



t Nineteenth Century Magazine, Nov. 1887, p. 667. See also " Darwinism," 1889, p. 456. 



