372 MAN AND THE GLACIAL PERIOD. 



studying them. The judgment of Mortillet is that twenty- 

 two specimens exhibited unmistakable traces of intentional 

 chipping, in which opinion I entirely concur. Only nine, 

 however, were represented as coming from the Miocene, 

 some of which showed on their surface an incrustation of 

 grit, which was claimed as proof of their origin. But the 

 opinion was freely expressed that, even if they really came 

 from the Miocene deposits, they might have penetrated into 

 them from the surface, through cracks, and thus have be- 

 come so incrusted. It was accordingly resolved to hold the 

 next international congress of prehistoric archaeologists at 

 Lisbon, in 1880, mainly for the purpose of settling this ques- 

 tion, if possible, by an investigation conducted upon the spot. 

 In the course of a visit made at that time to Otta, several 

 artificial specimens were found on the surface by different 

 searchers, but Professor Bellucci, of Perugia, was fortunate 

 enough to discover a flint flake in situ, still so closely im- 

 bedded in the deposit that it required to be detached by a 

 hammer. There is no question that this object was actually 

 found in a Miocene deposit, but unfortunately it belongs to 

 the doubtful category of external flakes, which, although 

 they exhibit the " bulb of percussion, " have no other sure 

 indication that they are the work of man.* As such bulbs 

 can be produced by natural causes, some stronger proof than 

 this of the existence of Tertiary man is demanded. 



These are all the localities in Europe claimed by Mortillet 

 to have furnished such evidence, but he thinks a strong con- 

 firmation of it is afforded by certain discoveries made in the 

 auriferous gravels of California. I will not occupy space 

 here in repeating arguments I have brought forward else- 

 where to show the utter insufficiency of this evidence to 

 prove the existence of man on the Pacific coast of our conti- 

 nent during the Pliocene period, f They may all be summed 

 up in the words of Le Conte : " The doubts in regard to this 



* It has been figured by Bellucci, Archivio per V Anthropologics 

 e la Etnologia di Firenze, tome xi, p. 12, tav. iv, fig. 2. To me it 

 possesses no value as evidence. 



f Tlie Prehistoric Archaeology of North America, Narrative and 

 Critical History of America, vol. i, pp. 850-356. 



