﻿162 
  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  formations, 
  the 
  northern 
  part 
  of 
  Summit 
  being 
  included 
  in 
  the 
  

   Hamilton. 
  

  

  Emmons 
  discussed 
  the 
  rocks 
  at 
  Jefferson 
  to 
  some 
  extent 
  under 
  

   the 
  heading 
  of 
  the 
  "Catskill 
  group," 
  though 
  he 
  apparently 
  cor- 
  

   related 
  them 
  with 
  the 
  Chemung. 
  He 
  said, 
  " 
  Near 
  the 
  village, 
  we 
  

   discovered 
  the 
  same 
  fossils 
  as 
  those 
  of 
  Gilboa, 
  namely, 
  the 
  

   Cypricardia, 
  Tentactdites, 
  Orthis, 
  etc. 
  Besides 
  the 
  strata 
  of 
  

   crushed 
  vegetables 
  and 
  the 
  diagonal 
  stratification 
  already 
  men- 
  

   tioned, 
  Mr 
  Hall 
  has 
  discovered 
  a 
  scale 
  of 
  the 
  fish 
  characteristic 
  

   of 
  the 
  Old 
  Eed 
  sandstone. 
  In 
  these 
  discoveries 
  we 
  have 
  the 
  facts 
  

   which 
  have 
  settled 
  the 
  character 
  and 
  age 
  of 
  the 
  rocks 
  in 
  the 
  

   southern 
  part 
  of 
  Schoharie, 
  Albany, 
  and 
  those 
  of 
  Greene 
  and 
  

   Delaware 
  counties. 
  They 
  form 
  one 
  series 
  of 
  rocks, 
  which 
  may 
  

   be 
  traced 
  south, 
  southwest 
  and 
  west, 
  through 
  the 
  southern 
  tier 
  

   of 
  counties; 
  and 
  as 
  a 
  few 
  fossils 
  of 
  the 
  Chemung 
  narrows 
  have 
  

   been 
  found 
  in 
  Gilboa, 
  we 
  are 
  able 
  to 
  connect 
  the 
  series 
  with 
  

   distant 
  points 
  west. 
  The 
  Chemung 
  group, 
  which 
  had 
  been 
  

   supposed 
  to 
  be 
  confined 
  to 
  the 
  southwestern 
  counties, 
  has 
  been 
  

   proved, 
  by 
  the 
  discovery 
  of 
  fossils, 
  to 
  occupy 
  a 
  place 
  also 
  at 
  the 
  

   base 
  of 
  the 
  Catskill 
  series. 
  Of 
  the 
  Dipleura 
  dekayi 
  [Homalonotus 
  

   dekayi], 
  Microdon 
  lellistriata, 
  Cypricardia 
  angulata, 
  the 
  latter 
  

   is 
  credited 
  to 
  Chemung 
  narrows, 
  while 
  the 
  two 
  former 
  are 
  well 
  

   known 
  Hamilton 
  fossils; 
  these, 
  with 
  several 
  others, 
  occur 
  500 
  

   feet 
  above 
  strata 
  which 
  have 
  hitherto 
  been 
  regarded 
  as 
  belong- 
  

   ing 
  exclusively 
  to 
  the 
  Catskill 
  series."* 
  

  

  XXVII 
  B 
  1 
  . 
  On 
  the 
  hill 
  to 
  the 
  south 
  of 
  Jefferson 
  and 
  Middle 
  

   brook 
  is 
  a 
  prominent 
  ledge 
  of 
  massive 
  coarse 
  gray 
  to 
  greenish 
  

   sandstone, 
  with 
  reddish 
  sandstone 
  at 
  the 
  top, 
  which 
  is 
  about 
  70 
  

   feet 
  above 
  the 
  village 
  hotel. 
  This 
  ledge 
  in 
  all 
  its 
  lithologic 
  char- 
  

   acters 
  is 
  like 
  the 
  Oneonta 
  sandstone. 
  Loose 
  on 
  the 
  ground 
  at 
  

   this 
  locality 
  but 
  apparently 
  from 
  this 
  ledge 
  are 
  blocks 
  contain- 
  

   ing 
  Spirifer 
  mesastrialis 
  Hall, 
  some 
  of 
  which 
  contain 
  large 
  num- 
  

   bers 
  of 
  specimens 
  ; 
  Bellerophon 
  sp. 
  and 
  a 
  scale 
  " 
  belonging 
  in 
  all 
  

   probability 
  to 
  Eoloptychius 
  americanus 
  Leidy 
  " 
  according 
  to 
  

   Dr 
  Eastman 
  were 
  also 
  found. 
  The 
  top 
  of 
  the 
  ledge 
  shows 
  quite 
  

  

  a 
  Agriculture 
  of 
  New 
  York. 
  1846. 
  1 
  : 
  196. 
  

  

  