﻿THE 
  GEOLOGICAL 
  HISTORY 
  OF 
  NEW 
  YORK 
  STATE 
  57 
  

  

  which 
  extend 
  from 
  the 
  Catskill 
  mountains 
  to 
  western 
  New 
  

   York. 
  

  

  Except 
  for 
  the 
  comparatively 
  thin 
  Tully 
  formation, 
  the 
  limestone 
  

   is 
  confined 
  to 
  the 
  Lower 
  Devonic 
  and 
  the 
  lower 
  part 
  is 
  not 
  more 
  

   than 
  a 
  few 
  hundred 
  feet 
  thick. 
  Thus 
  the 
  great 
  bulk 
  of 
  Devonic 
  

   rock 
  lies 
  above 
  this 
  limestone 
  and 
  consists 
  of 
  shales 
  and 
  sandstones 
  

   piled 
  layer 
  upon 
  layer. 
  These 
  latter 
  rocks 
  are 
  clearly 
  land-derived 
  

   sediments 
  which 
  were 
  washed 
  into 
  the 
  Devonic 
  sea 
  by 
  streams 
  from 
  

   the 
  Taconics 
  and 
  also 
  probably 
  from 
  land 
  areas 
  which 
  are 
  known 
  

   to 
  have 
  existed 
  to 
  the 
  north 
  in 
  Canada. 
  

  

  The 
  Devonic 
  strata, 
  from 
  oldest 
  to 
  youngest, 
  abound 
  in 
  the 
  fossils 
  

   of 
  marine 
  organisms, 
  and 
  some 
  fossil 
  land 
  plants 
  have 
  also 
  been 
  

   found. 
  Looked 
  upon 
  in 
  a 
  broad 
  way, 
  Devonic 
  life 
  was 
  much 
  like 
  

   that 
  of 
  the 
  Siluric, 
  though 
  certain 
  fundamental 
  differences 
  are 
  to 
  

   be 
  noted. 
  Thus 
  the 
  Devonic 
  furnishes 
  the 
  first 
  really 
  authentic 
  evi- 
  

   dence 
  of 
  the 
  existence 
  of 
  land 
  plants. 
  Such 
  plants 
  as 
  ferns, 
  lyco- 
  

   pods 
  (club 
  mosses), 
  and 
  equisetae 
  (horse 
  tails) 
  grew 
  to 
  be 
  large 
  

   treelike 
  forms 
  and 
  in 
  considerable 
  profusion. 
  Remains 
  of 
  these 
  

   have 
  been 
  found 
  in 
  the 
  Devonic 
  strata 
  in 
  New 
  York. 
  All 
  of 
  them 
  

   belonged 
  to 
  the 
  very 
  simple, 
  nonflowering 
  plants 
  and 
  were 
  closely 
  

   related 
  to 
  the 
  plants 
  of 
  the 
  next 
  succeeding 
  Carbonic 
  (coal) 
  period. 
  

   Among 
  the 
  fossil 
  animals 
  especially 
  abundant 
  in 
  the 
  Devonic 
  rocks 
  

   of 
  the 
  State 
  are: 
  sponges, 
  corals, 
  echinoderms 
  (star 
  fishes), 
  brachi- 
  

   opods, 
  mollusks 
  (including 
  the 
  bivalves, 
  gastropods, 
  and 
  cephalo- 
  

   pods), 
  and 
  arthropods 
  (including 
  trilobites 
  and 
  eurypterids). 
  The 
  

   graptolites 
  became 
  extinct 
  during 
  the 
  early 
  Devonic. 
  One 
  of 
  the 
  

   remarkable 
  features 
  of 
  the 
  life 
  was 
  the 
  great 
  abundance 
  and 
  variety 
  

   of 
  fishes, 
  so 
  that 
  this 
  period 
  is 
  commonly 
  referred 
  to 
  as 
  the 
  " 
  Age 
  

   of 
  Fishes." 
  From 
  the 
  zoological 
  standpoint 
  all 
  the 
  fishes 
  were 
  of 
  

   simple 
  types, 
  the 
  true 
  bony 
  skeletons 
  of 
  modern 
  fishes 
  being 
  entirely 
  

   absent. 
  Devonic 
  fish 
  remains 
  in 
  considerable 
  numbers 
  have 
  been 
  

   found 
  in 
  the 
  State. 
  

  

  Carbonic 
  strata 
  are 
  only 
  very 
  sparingly 
  represented 
  in 
  New 
  York, 
  

   there 
  being 
  a 
  few 
  small 
  outlying 
  masses 
  in 
  the 
  southwestern 
  portion 
  

   of 
  the 
  State 
  (Cattaraugus 
  and 
  Allegany 
  counties). 
  Immediately 
  

   southward, 
  in 
  Pennsylvania, 
  Carbonic 
  strata 
  are 
  developed 
  on 
  a 
  

   great 
  scale 
  so 
  we 
  can 
  be 
  certain 
  that 
  the 
  Carbonic 
  sea 
  spread 
  over 
  

   the 
  southern 
  border 
  of 
  New 
  York 
  State. 
  It 
  is 
  quite 
  possible 
  that 
  

   this 
  sea 
  extended 
  over 
  most 
  of 
  southern 
  New 
  York, 
  but 
  positive 
  

   evidence, 
  due 
  to 
  absence 
  of 
  strata, 
  is 
  lacking. 
  

  

  The 
  Permic 
  is 
  the 
  last 
  great 
  period 
  of 
  the 
  Paleozoic 
  era, 
  but 
  

   rocks 
  of 
  that 
  age 
  are 
  nowhere 
  present 
  in 
  New 
  York 
  State. 
  

  

  