﻿On 
  some 
  Rostro-carinate 
  Flint 
  Implements 
  and 
  Allied 
  Forms. 
  331 
  

  

  terrace 
  gravels, 
  which 
  exhibit 
  transition, 
  in 
  form 
  and 
  sculptural 
  treatment, 
  

   between 
  the 
  typical 
  " 
  rostro-carinate 
  " 
  and 
  the 
  large 
  platessiform 
  tongue- 
  

   like 
  implements 
  of 
  Chellean 
  age. 
  

  

  It 
  is 
  impossible 
  to 
  assign 
  any 
  of 
  these 
  later 
  " 
  rostro-carinate 
  " 
  specimens 
  to 
  the 
  

  

  Fig. 
  1 
  (From 
  the 
  ' 
  Phil. 
  Trans., 
  1 
  B, 
  May, 
  1912). 
  — 
  Diagrams 
  showing 
  the 
  ideal 
  form 
  aimed 
  at 
  

   by 
  the 
  makers 
  of 
  the 
  rostro-carinate 
  flint 
  implements 
  or 
  " 
  Eagles' 
  Beaks." 
  A, 
  anterior 
  ; 
  

   P, 
  posterior 
  ; 
  R, 
  right 
  ; 
  L, 
  left. 
  (In 
  the 
  present 
  memoir 
  I 
  use 
  the 
  term 
  " 
  carina 
  " 
  in 
  

   place 
  of 
  " 
  keel," 
  and 
  sometimes 
  refer 
  to 
  the 
  " 
  dorsal 
  plane" 
  as 
  the 
  " 
  dorsal 
  platform.") 
  

  

  geological 
  horizon 
  or 
  deposit 
  corresponding 
  to 
  the 
  date 
  or 
  period 
  ai 
  vjhich 
  they 
  

   vjere 
  fabricated 
  by 
  man. 
  Some 
  have 
  been 
  found 
  in 
  such 
  positions 
  and 
  such 
  

   beds 
  that 
  it 
  is 
  possible 
  that 
  they 
  were 
  manufactured 
  at 
  the 
  same 
  date 
  or 
  

   period 
  as 
  were 
  those 
  found 
  beneath 
  the 
  Red 
  Crag 
  and 
  the 
  Norwich 
  Crag. 
  

  

  