PREHISTORIC CLASSIFICATION 275 



been destroyed by subaerial denudation in the process of 

 valley formation is much greater than is sometimes realised. 

 Secondly, that very generally implements are older — very 

 often very much more so — than the deposit in which they are 

 found. The first question that naturally suggests itself is, 

 where are those uncaptured surface palseoliths? They must 

 be on or near the surface still, and, having been subject to the 

 same processes as the other flints associated with them, will 

 be subject to the same set of surface changes. But the 

 antiquity of anything found at the surface, especially if altera- 

 tion processes have not been very operative, or if the specimens 

 have become " whitened " (cretaised or porcellanised), is pre- 

 cluded by the ideas that have associated themselves with 

 the term " palaeolithic. " It is therefore certain that the term 

 palaeolithic cannot be confined to the iron-stained (jasperised) 

 specimens of the drift ; nor can it be excluded from surface 

 finds : consequently the terms palaeolithic and neolithic, rough 

 and polished stone ages, in the light of more recent discoveries 

 are misleading, and should now be relegated to the pension 

 list. It is true an attempt might be made to limit and define 

 the term neolithic, but it would always be confused with its 

 old equivalent, polished stone age (despite the fact that polished 

 weapons belong to metal ages), or to things not found in an old 

 river-drift. Further, so much more material from so many 

 different sources has so enlarged our knowledge of late years, 

 that we require a far more extensive and comprehensive 

 scheme of classification. Probably the first real light that 

 was thrown upon post-miocene succession came from the 

 palaeontological evidence. In their exhaustive researches on 

 the pleistocene and holocene mollusca, Messrs. B. B. Wood- 

 ward and A. S. Kennard have shown from time to time that 

 the palaeo-neolithic gap could be largely filled up by the 

 mollusca of various sections, that the jump from the extinct 

 to the wholly recent did not really exist, and that an orderly 

 consecutive chronological series could be established from the 

 pliocene to the recent. Then came the splendid work of 

 Hinton on the vertebrates, telling of the same orderly succes- 

 sion. During recent years the science of lithoclasiology has 

 developed, and this, in showing the natural history of the flint- 

 worker's art, establishes this same orderly sequence. 



It did not require many years of either practical field work 



