﻿350 
  

  

  Sir 
  E. 
  Ray 
  Lankester. 
  On 
  some 
  

  

  anterior 
  cutting 
  edge 
  of 
  the 
  ventral 
  plane. 
  This 
  fracture 
  probably 
  existed 
  

   before 
  this 
  lump 
  of 
  flint 
  had 
  fallen 
  into 
  the 
  hands 
  of 
  a 
  human 
  artificer. 
  

   The 
  rest 
  of 
  the 
  surface 
  presents 
  a 
  beautiful 
  combination 
  of 
  milky 
  greys 
  and 
  

   browns 
  (due 
  to 
  iron-stain 
  and 
  decomposition*) 
  and 
  in 
  some 
  parts 
  a 
  brilliant 
  

   polish 
  (not 
  rightly 
  called 
  "glaze"). 
  Very 
  numerous 
  shallow 
  and 
  broad 
  

   scratches 
  cross 
  one 
  another 
  on 
  the 
  flat 
  surfaces 
  of 
  the 
  flint. 
  I 
  am 
  unable 
  to 
  

   decide 
  whether 
  they 
  should 
  be 
  attributed 
  to 
  glacial 
  agency 
  or 
  to 
  less 
  forcible 
  

   sand 
  scratching, 
  which 
  could, 
  no 
  doubt, 
  cause 
  markings 
  on 
  flint 
  which 
  had 
  

   been 
  exposed 
  to 
  the 
  softening 
  effect 
  of 
  atmospheric 
  weathering. 
  

  

  Some 
  day 
  we 
  may 
  hope 
  to 
  see 
  a 
  careful 
  and 
  really 
  adequate 
  study 
  of 
  the 
  

   scratching, 
  polishing, 
  staining, 
  and 
  other 
  markings 
  of 
  flints 
  from 
  different 
  

   deposits 
  and 
  of 
  different 
  antecedents, 
  also 
  a 
  study 
  of 
  the 
  fracture 
  of 
  flint 
  by 
  

   heat, 
  by 
  cold, 
  by 
  natural 
  blows, 
  by 
  humanly 
  directed 
  blows 
  — 
  a 
  very 
  large 
  

   subject, 
  including 
  hinge-fracture 
  and 
  an 
  endless 
  variety 
  of 
  " 
  rippling 
  " 
  — 
  but 
  

   not 
  admitting 
  the 
  possibility 
  of 
  the 
  fracture 
  of 
  flint 
  by 
  the 
  weight 
  of 
  super- 
  

   incumbent 
  water 
  or 
  sand. 
  

  

  All 
  the 
  specimens 
  figured 
  in 
  this 
  paper, 
  with 
  the 
  exception 
  of 
  Mr. 
  Moir's 
  

   " 
  Whitton-Mid-Glacial 
  typical 
  form 
  " 
  (figs. 
  5a, 
  5b, 
  5c) 
  and 
  Dr. 
  Peake's 
  Sonning 
  

   uncinate 
  (figs. 
  13 
  and 
  14), 
  are 
  now 
  presented 
  to 
  the 
  British 
  Museum 
  

   Department 
  of 
  Ethnology 
  and 
  Mediaeval 
  Antiquities, 
  where 
  they 
  can 
  be 
  

   examined 
  alongside 
  of 
  the 
  rostro-carinates 
  previously 
  described 
  by 
  me, 
  and 
  

   kindly 
  presented 
  by 
  their 
  owners 
  to 
  the 
  national 
  museum, 
  chief 
  among 
  whom 
  

   is 
  Mr. 
  Reid 
  Moir, 
  of 
  Ipswich. 
  

  

  Theoretical 
  Suggestion. 
  

   In 
  conclusion 
  I 
  wish 
  to 
  point 
  out 
  that 
  although 
  it 
  is 
  not 
  possible 
  in 
  the 
  

   present 
  state 
  of 
  our 
  knowledge 
  to 
  gain 
  direct 
  evidence 
  of 
  the 
  historical 
  

   relationship 
  and 
  derivation, 
  one 
  from 
  another, 
  of 
  the 
  early 
  forms 
  of 
  flint 
  

   implements 
  — 
  there 
  is 
  yet 
  sufficient 
  ground 
  for 
  holding 
  it 
  to 
  be 
  probable 
  that 
  

   the 
  conception 
  of 
  a 
  " 
  form 
  " 
  or 
  " 
  type 
  " 
  to 
  be 
  aimed 
  at 
  by 
  the 
  worker 
  in 
  flint, 
  

   developed 
  gradually, 
  and 
  that 
  there 
  is 
  a 
  real 
  connection 
  of 
  the 
  various 
  forms 
  

   which 
  were 
  manufactured. 
  It 
  is 
  legitimate 
  to 
  assume 
  as 
  a 
  hypothesis 
  that 
  

   the 
  most 
  generalised 
  form 
  — 
  the 
  rostro-carinate 
  witb 
  a 
  ventral 
  "planing" 
  

   surface 
  — 
  cutting 
  latero-ventral 
  edge, 
  sharp-cutting 
  carina 
  or 
  keel 
  and 
  pointed 
  

   rostrum 
  for 
  grubbing 
  and 
  boring 
  — 
  in 
  fact 
  the 
  form 
  shown 
  in 
  fig. 
  1, 
  is, 
  if 
  not 
  

   the 
  initial 
  conception, 
  yet 
  at 
  any 
  rate 
  that 
  to 
  which 
  all 
  others 
  are 
  connected. 
  

  

  * 
  The 
  whitening 
  of 
  flint 
  by 
  solution 
  of 
  the 
  opal 
  which 
  cements 
  its 
  microcrystalline 
  

   siliceous 
  particles 
  needs 
  some 
  other 
  name 
  than 
  " 
  decomposition." 
  I 
  propose 
  to 
  call 
  it 
  

   " 
  lactescence 
  " 
  and 
  to 
  describe 
  the 
  flint 
  thus 
  changed 
  as 
  " 
  lacteate 
  " 
  or 
  " 
  milky." 
  

  

  