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  Lahee 
  — 
  New 
  Fossiliferous 
  Horizon 
  and 
  Underlying 
  

  

  shale 
  beds, 
  concealed 
  for 
  the 
  most 
  part 
  by 
  the 
  vegetation. 
  

   And 
  stratigraphically 
  above 
  them 
  is 
  the 
  second 
  great 
  mass 
  of 
  

   arkose, 
  the 
  ' 
  Fitch 
  Hill 
  arkose.' 
  Just 
  what 
  structural 
  relations 
  

   this 
  rock 
  has 
  to 
  those 
  underlying, 
  we 
  cannot 
  say. 
  Contacts 
  

   are 
  not 
  exposed. 
  It 
  appears 
  to 
  be 
  in 
  conformity. 
  It 
  is 
  very 
  

   like 
  the 
  basal 
  arkose, 
  — 
  hard, 
  dense, 
  and 
  spotted 
  with 
  white 
  

   grains 
  of 
  feldspar 
  which 
  compose 
  about 
  half 
  of 
  the 
  rock. 
  It 
  

   is 
  more 
  uniform 
  in 
  texture 
  than 
  the 
  basal 
  arkose, 
  its 
  grain 
  

   averaging 
  1/15/ 
  No 
  signs 
  of 
  bedding 
  nor 
  of 
  limestone 
  inclu- 
  

   sions 
  were 
  seen. 
  Microscopically, 
  also, 
  it 
  is 
  similar 
  to 
  the 
  

   lower 
  arkose. 
  

  

  Both' 
  of 
  the 
  sills 
  are 
  composed 
  of 
  a 
  coarse, 
  massive, 
  unsheared 
  

   rock, 
  formerly 
  consisting 
  of 
  hornblende 
  and 
  plagioclase. 
  The 
  

   hornblende 
  has 
  been 
  replaced. 
  by 
  zoisite, 
  calcite, 
  and 
  chlorite. 
  

   These 
  intrusions 
  grow 
  much 
  finer 
  toward 
  their 
  upper 
  and 
  

   lower 
  contacts. 
  In 
  spots 
  they 
  have 
  metamorphosed 
  the 
  sedi- 
  

   ments. 
  

  

  The 
  Fitch 
  Hill 
  arkose 
  is 
  overlain 
  by 
  a 
  thick 
  body 
  of 
  nicely 
  

   banded 
  mudstones 
  or 
  argillites. 
  The 
  bands, 
  of 
  lighter 
  and 
  

   darker 
  gray, 
  are 
  from 
  1/2 
  inch 
  to 
  3 
  inches 
  wide, 
  and 
  may 
  be 
  

   traced 
  for 
  many 
  yards. 
  The 
  lighter 
  bands 
  are 
  fine 
  argillaceous 
  

   sandstone, 
  and 
  the 
  darker, 
  medium 
  to 
  fine-grained 
  mudstone. 
  

   They 
  are 
  very 
  regular, 
  but 
  sometimes 
  show 
  local 
  crumpling 
  

   on 
  a 
  small 
  scale. 
  Neither 
  this 
  formation 
  nor 
  the 
  overlying 
  

   dark 
  gray 
  sandstone 
  are 
  of 
  immediate 
  concern 
  for 
  us. 
  Their 
  

   importance 
  will 
  be 
  explained 
  later. 
  

  

  Geology 
  of 
  the 
  Blueberry 
  Mountain 
  Series 
  Southwest 
  of 
  

   Fitch 
  Hill. 
  

  

  Distribution. 
  — 
  We 
  have 
  previously 
  stated 
  that 
  the 
  Lyman 
  

   schists 
  pass 
  off 
  the 
  map 
  (fig. 
  2) 
  and 
  that 
  the 
  Fitch 
  Hill 
  granite 
  

   gneiss 
  narrows 
  and 
  finally 
  disappears 
  south 
  westward. 
  

  

  On 
  the 
  northern 
  side 
  of 
  Fitch 
  Hill 
  the 
  limestone 
  is 
  a 
  valley- 
  

   maker 
  (not 
  shown 
  by 
  the 
  contours). 
  Without 
  entering 
  into 
  

   great 
  detail 
  of 
  description, 
  we 
  may 
  say 
  that 
  this 
  limestone 
  is 
  

   thought 
  to 
  underlie 
  the 
  valley 
  which 
  is 
  just 
  northwest 
  of 
  Blue- 
  

   berry 
  Mt., 
  Bald 
  Hill, 
  and 
  the 
  hill 
  in 
  the 
  extreme 
  western 
  

   corner 
  of 
  the 
  map. 
  This 
  valley 
  contains 
  Young's 
  Pond. 
  Asso- 
  

   ciated 
  with 
  the 
  limestone 
  are 
  the 
  other 
  members 
  of 
  the 
  basal 
  

   series 
  ; 
  but 
  there 
  are 
  exceedingly 
  few 
  outcrops 
  of 
  these 
  rocks. 
  

   Locality 
  26 
  (sec. 
  D, 
  fig. 
  3) 
  is 
  an 
  outcrop 
  of 
  coarse 
  feldspathic 
  

   grit 
  resembling 
  the 
  Fitch 
  Hill 
  arkose. 
  Half 
  a 
  mile 
  southwest 
  

   of 
  this 
  a 
  large 
  glacial 
  bowlder 
  of 
  conglomerate, 
  with 
  ten 
  or 
  

   twelve 
  limestone 
  pebbles 
  in 
  it, 
  was 
  found 
  ; 
  and 
  calcareous 
  

   schist 
  is 
  exposed 
  a 
  few 
  hundred 
  feet 
  away. 
  Limestone 
  and 
  

   calcareous 
  grits 
  outcrop 
  at 
  Locs. 
  42 
  and 
  43. 
  Here 
  the 
  lime- 
  

  

  