﻿Report 
  of 
  the 
  State 
  Geologist. 
  237 
  

  

  Along 
  the 
  bed 
  of 
  the 
  stream 
  which 
  is 
  crossed 
  by 
  the 
  Lake 
  

   Erie 
  and 
  Western 
  railroad 
  at 
  Griswold's 
  there 
  is 
  a 
  good 
  natural 
  

   section 
  through 
  the 
  upper 
  Hamilton 
  shales 
  and 
  also 
  along 
  

   Eleven 
  Mile 
  creek, 
  two 
  miles 
  west 
  of 
  Darien 
  Centre, 
  Genesee 
  

   county. 
  

  

  From 
  321 
  to 
  333 
  feet 
  below 
  the 
  surface 
  in 
  the 
  Livonia 
  salt 
  

   shaft 
  the 
  rock 
  is 
  much 
  less 
  fossiliferous, 
  darker 
  and 
  harder. 
  

  

  From 
  333 
  to 
  353 
  feet 
  the 
  rock 
  was 
  soft, 
  bluish-gray 
  shale, 
  

   with 
  some 
  dark 
  layers. 
  The 
  bed 
  contains 
  very 
  little 
  pyrites 
  and 
  

   concretions 
  are 
  rare. 
  

  

  The 
  presence 
  of 
  many 
  fine 
  specimens 
  of 
  the 
  lamellibranchs 
  

   Grammy 
  sia 
  bisulcata, 
  Orthonota 
  undulata, 
  Glyptodesma 
  erectum 
  

   and 
  entire 
  individuals 
  of 
  Homolonotus 
  DeKayi 
  and 
  other 
  

   trilobites 
  makes 
  this 
  bed 
  exceedingly 
  interesting. 
  

  

  From 
  353 
  to 
  380 
  feet, 
  the 
  depth 
  at 
  which 
  the 
  measurements 
  

   and 
  records 
  were 
  begun, 
  the 
  rock 
  passed 
  through 
  was 
  bluish, 
  

   medium 
  s< 
  >ft 
  shale 
  of 
  much 
  the 
  same 
  character 
  as 
  the 
  " 
  Moscow 
  

   shales," 
  though 
  fossils 
  are 
  much 
  less 
  abundant 
  and 
  concretions 
  

   are 
  rare. 
  At 
  the 
  crossing 
  of 
  a 
  small 
  stream 
  formerly 
  known 
  as 
  

   " 
  Jay 
  cox 
  run, 
  " 
  by 
  the 
  Avon 
  road, 
  two 
  and 
  one-half 
  miles 
  north 
  

   of 
  Geneseo, 
  this 
  bed 
  is 
  much 
  richer 
  in 
  fossils 
  than 
  at 
  the 
  shaft 
  

  

  From 
  the 
  depth 
  of 
  386 
  to 
  440 
  feet 
  the 
  rock 
  taken 
  out 
  of 
  the 
  

   shaft 
  was 
  richly 
  fossiliferous 
  and 
  several 
  thin 
  layers 
  of 
  limestone 
  

   with 
  shales 
  separating 
  them 
  were 
  penetrated. 
  

  

  These 
  limestones 
  are 
  exposed 
  in 
  Menteth's 
  and 
  Tichenor's 
  

   gullies, 
  on 
  Canandaigua 
  lake, 
  and 
  at 
  the 
  high 
  falls 
  in 
  the 
  ravine 
  

   two 
  and 
  one-half 
  miles 
  north 
  of 
  Geneseo. 
  They 
  contain 
  frag- 
  

   ments 
  of 
  crinoid 
  columns 
  and 
  plates, 
  and 
  the 
  lower 
  one 
  bears 
  so 
  

   close 
  a 
  resemblance 
  to 
  the 
  limestone 
  of 
  the 
  encrinal 
  band 
  that 
  it 
  

   is 
  not 
  always 
  easy 
  to 
  identify 
  them 
  unless 
  the 
  adjacent 
  strata 
  

   are 
  accessible 
  for 
  examination. 
  

  

  From 
  440 
  to 
  547 
  feet 
  the 
  soft 
  bluish 
  shale 
  encountered 
  in 
  

   sinking 
  the 
  shaft 
  continued 
  ^ 
  ith 
  slight 
  changes. 
  Fossils 
  were 
  

   generally 
  not 
  so 
  abundant 
  as 
  above, 
  though 
  some 
  horizons 
  

   afforded 
  good 
  specimens. 
  

  

  The 
  encrinal 
  limestone 
  was 
  reached 
  - 
  at 
  560 
  feet 
  from 
  the 
  

   collar 
  of 
  the 
  shaft, 
  and 
  280 
  feet 
  from 
  the 
  top 
  of 
  the 
  Hamilton 
  

   group. 
  

  

  