﻿KEV. 
  W. 
  DOWNES 
  0^ 
  THE 
  BLACKDOWN 
  BEDS. 
  83 
  

  

  beds 
  of 
  this 
  character 
  extend 
  very 
  nearly 
  down 
  to 
  the 
  base 
  of 
  the 
  

   series, 
  while 
  at 
  Blackdown 
  they 
  only 
  occur 
  at 
  the 
  top, 
  immediately 
  

   beneath 
  the 
  chert 
  gravel. 
  

  

  Bed 
  13. 
  As 
  a 
  bed 
  this 
  can 
  only 
  be 
  identified 
  at 
  Haldon, 
  where 
  it 
  

   is 
  found 
  in 
  many 
  places. 
  It 
  is 
  the 
  " 
  littoral 
  concrete 
  " 
  of 
  Prof. 
  

   Duncan, 
  celebrated 
  for 
  its 
  coral 
  fauna. 
  In 
  a 
  sand-pit 
  at 
  the 
  road- 
  

   side 
  on 
  the 
  east 
  of 
  Great 
  Haldon, 
  on 
  the 
  Exeter 
  and 
  Newton 
  road, 
  

   it 
  may 
  be 
  described 
  as 
  consisting 
  of 
  three 
  bands 
  of 
  fossil 
  shells 
  (for 
  

   the 
  most 
  part 
  broken) 
  in 
  a 
  basis 
  of 
  sand. 
  The 
  two 
  higher 
  bands 
  are 
  

   thin 
  and 
  insignificant, 
  but 
  the 
  third 
  or 
  lowest 
  is 
  about 
  1^ 
  foot 
  thick, 
  

   a 
  hard 
  jaspideous 
  mass 
  full 
  of 
  fossil 
  fragments. 
  I 
  detected 
  in 
  it 
  

   Ostrea 
  and 
  Exogyra 
  in 
  abundance, 
  Trigonia 
  Vicar 
  y 
  ana, 
  Lycett, 
  

   and 
  Vermieularia, 
  but 
  no 
  corals. 
  I 
  visited 
  the 
  place 
  twice, 
  the 
  

   second 
  time 
  with 
  Mr. 
  Champernowne, 
  but 
  neither 
  of 
  us 
  succeeded 
  in 
  

   finding 
  a 
  coral. 
  Judging 
  by 
  the 
  list 
  of 
  coral 
  species, 
  and 
  by 
  the 
  

   specimens 
  exhibited 
  by 
  dealers, 
  one 
  is 
  apt 
  to 
  be 
  much 
  misled 
  as 
  to 
  

   the 
  character 
  of 
  this 
  bed, 
  and 
  to 
  suppose 
  that 
  it 
  consists 
  largely 
  of 
  

   corals 
  and 
  Polyzoa. 
  The 
  truth 
  is 
  that 
  tons 
  of 
  the 
  material 
  might 
  

   have 
  to 
  be 
  removed 
  before 
  a 
  nest 
  of 
  corals 
  or 
  Polyzoa 
  would 
  be 
  found 
  ; 
  

   and 
  for 
  a 
  chance 
  comer 
  to 
  find 
  even 
  a 
  single 
  specimen 
  would 
  be 
  a 
  

   fortunate 
  circumstance. 
  No 
  such 
  bed 
  exists 
  at 
  Blackdown 
  ; 
  but 
  a 
  

   very 
  few 
  specimens 
  of 
  the 
  characteristic 
  fauna 
  have 
  been 
  found. 
  

   The 
  Blackdown 
  specimens 
  may 
  be 
  numbered 
  on 
  the 
  fingers. 
  Two 
  

   or 
  three 
  specimens 
  of 
  Trochosmilia 
  or 
  Smilotrochus, 
  one 
  of 
  (?) 
  Isas- 
  

   trcea, 
  and 
  one 
  or 
  two 
  corals 
  unnamed 
  complete 
  the 
  list, 
  so 
  far 
  as 
  

   Blackdown 
  is 
  concerned, 
  whereas 
  a 
  large 
  and 
  increasing 
  list 
  is 
  

   referred 
  to 
  Haldon 
  by 
  Prof. 
  Duncan, 
  who, 
  as 
  already 
  observed, 
  com- 
  

   pares 
  the 
  fauna 
  to 
  that 
  of 
  Gosau. 
  

  

  Bed 
  14. 
  At 
  Haldon, 
  above 
  the 
  " 
  littoral 
  concrete," 
  is 
  found 
  about 
  

   8 
  feet 
  of 
  schorlaceous 
  and 
  non-glauconitic 
  sand. 
  All 
  the 
  sand 
  below 
  

   this 
  is 
  more 
  or 
  less 
  glauconitic. 
  It 
  contains 
  a 
  few 
  fragments 
  of 
  

   Exogyra. 
  

  

  Bed 
  15. 
  Orbitolina-chert, 
  in 
  layers 
  6 
  feet, 
  is 
  seen 
  at 
  Smallacombe 
  

   Goyle, 
  Little 
  Haldon 
  ; 
  but 
  it 
  seems 
  to 
  occur 
  only 
  locally. 
  It 
  is 
  a 
  

   glassy 
  translucent 
  chert 
  weathering 
  to 
  a 
  dull 
  whitish 
  surface 
  : 
  it 
  is 
  

   hard 
  and 
  brittle 
  in 
  the 
  centre, 
  but 
  soft 
  and 
  earthy 
  on 
  the 
  weathered 
  

   exterior, 
  and 
  abounds 
  in 
  0. 
  concava, 
  Lam., 
  and 
  Lima 
  semisulcata, 
  Sow. 
  

   Bed 
  16. 
  Chert 
  gravel. 
  At 
  Blackdown 
  this 
  frequently 
  caps 
  the 
  

   hill. 
  It 
  is 
  found 
  in 
  a 
  clayey 
  matrix 
  intermixed 
  generally 
  with 
  very 
  

   vesicular 
  concretions 
  of 
  limonite. 
  The 
  latter 
  has 
  often 
  been 
  mis- 
  

   taken 
  for 
  iron 
  slag, 
  which 
  it 
  very 
  much 
  resembles 
  in 
  appearance. 
  But 
  

   as 
  it 
  can 
  be 
  seen 
  not 
  only 
  lying 
  round 
  the 
  old 
  and 
  present 
  chert-pits, 
  

   but 
  also 
  in 
  situ 
  in 
  precisely 
  the 
  same 
  condition, 
  the 
  tales 
  of 
  pre- 
  

   historic 
  bloomeries 
  founded 
  upon 
  this 
  evidence 
  rest 
  upon 
  a 
  very 
  

   questionable 
  foundation. 
  

  

  Bed 
  17. 
  Flint 
  gravel. 
  None 
  is 
  found 
  at 
  Blackdown, 
  I 
  believe, 
  to 
  

   the 
  north 
  of 
  Kentisbeare, 
  but 
  south 
  of 
  that 
  place 
  it 
  generally 
  caps 
  

   the 
  chert 
  gravel 
  without 
  being 
  mixed 
  with 
  it. 
  At 
  Blackdown 
  pro- 
  

   bably 
  it 
  never 
  much 
  exceeds 
  10 
  feet, 
  while 
  it 
  attains 
  a 
  thickness 
  of 
  

   30 
  feet 
  or 
  40 
  feet 
  at 
  Haldon. 
  The 
  springs 
  which 
  at 
  Blackdown 
  

  

  g2 
  

  

  