448 TROPICAL NATURE 



coveries should have been made in California rather than in 

 any other part of America is sufficiently apparent if we consider 

 the enormous amount of excavation of the Pliocene gravels in 

 the long-continued prosecution of gold-mining, and also the 

 probability that the region was formerly, as now, characterised 

 by a milder climate, and a more luxuriant perennial vegetation, 

 and was thus able to support a comparatively dense popula- 

 tion even in those remote times. Admitting that man did 

 inhabit the Pacific slope at the time indicated, the remains 

 appear to be of such a character as might be anticipated, and 

 present all the characteristics of genuine discoveries. 



Concluding Remarks on tJie Antiquity of Man 

 Even these Californian remains do not exhaust the proofs 

 of man's great antiquity in America, since we have the record 

 of another discovery which indicates that he may, possibly, 

 have existed at an even more remote epoch. Mr. E. L. 

 Berthoud has described the finding of stone implements of a 

 rude type in the Tertiary gravels of the Crow Creek, Colorado. 

 Some shells were obtained from the same gravels, which were 

 determined by Mr. T. A. Conrad to be species which are 

 " certainly not later than Older Pliocene, or possibly Miocene." 

 The account of this remarkable discovery, published in the 

 Proceedings of the Academy of Natural Sciences of Philadelphia, 

 1872, is not very clear or precise, and it is much to be wished 

 that some competent geologist would examine the locality. 

 But the series of proofs of the existence of man by the dis- 

 covery of his remains or his works going back step by step to 

 the Pliocene period, which have been now briefly enumerated, 

 takes away from this alleged discovery the extreme im- 

 probability which would be held to attach to it at the time 

 when it was made. 



It is surely now time that this extreme scepticism as to 

 any extension of the human period beyond that reached by 

 Boucher de Perthes, half a century ago, should give way to 

 the ever -increasing body of facts on the other side of the 

 question. Geologists and anthropologists must alike feel that 

 there is a great, and at present inexplicable, chasm interven- 

 ing between the earliest remains of man and those of his 

 animal predecessors that the entire absence of the " missing 



