﻿Geology 
  and 
  Mineralogy. 
  299 
  

  

  The 
  latter 
  half 
  of 
  the 
  volume 
  is 
  devoted 
  to 
  the 
  Paleontology 
  

   of 
  the 
  Park 
  area 
  and 
  consists 
  of 
  three 
  chapters, 
  the 
  Paleozoic 
  

   fossils, 
  the 
  Mesozoic 
  invertebrates, 
  and 
  the 
  Mesozoic 
  and 
  Tertiary 
  

   flora. 
  

  

  The 
  Paleozoic 
  sediments, 
  clearly 
  recognizable 
  by 
  their 
  fossil 
  

   contents, 
  belong 
  to 
  the 
  Cambrian, 
  Devonian, 
  and 
  Lower 
  Car- 
  

   boniferous 
  terranes. 
  The 
  Cambrian 
  fauna 
  of 
  about 
  thirty 
  species 
  

   is 
  described 
  by 
  the 
  Director 
  of 
  the 
  Survey, 
  Charles 
  D. 
  Walcott. 
  

   Several 
  of 
  the 
  species 
  are 
  new 
  to 
  science, 
  and 
  one 
  new 
  genus, 
  

   Haguia, 
  is 
  referred 
  to 
  a 
  primitive 
  type 
  of 
  Archceocyathince. 
  

  

  The 
  Devonian 
  and 
  Lower 
  Carboniferous 
  collections 
  are 
  dis- 
  

   cussed 
  by 
  Dr. 
  G. 
  H. 
  Girty. 
  The 
  Devonian 
  fauna 
  is 
  a 
  meager 
  one, 
  

   and 
  the 
  fossils 
  are 
  generally 
  poorly 
  preserved. 
  The 
  Madison 
  

   limestone, 
  representing 
  probably 
  the 
  major 
  portion 
  of 
  the 
  Missis- 
  

   sippian 
  with 
  Kinderhook 
  affinities, 
  contains 
  a 
  much 
  richer 
  and 
  

   more 
  varied 
  fauna 
  of 
  seventy-nine 
  species. 
  

  

  The 
  Mesozoic 
  invertebrates 
  were 
  studied 
  by 
  T. 
  W. 
  Stanton. 
  

   Thirty-one 
  species 
  are 
  recognized 
  from 
  the 
  Cretaceous, 
  forty-six 
  

   from 
  the 
  Jurassic, 
  and 
  one 
  from 
  beds 
  of 
  supposed 
  Triassic 
  age. 
  

   The 
  Jurassic 
  fauna 
  is 
  the 
  most 
  important, 
  and 
  in 
  number 
  of 
  

   species 
  it 
  compares 
  favorably 
  with 
  the 
  Jurassic 
  of 
  other 
  parts 
  of 
  

   the 
  Rocky 
  Mountain 
  region. 
  

  

  The 
  fossil 
  flora 
  of 
  the 
  Park 
  by 
  F. 
  H. 
  Knowlton 
  forms 
  the 
  sub- 
  

   ject 
  of 
  the 
  last 
  chapter, 
  and 
  is 
  an 
  important 
  geological 
  and 
  paleo- 
  

   botanical 
  contribution. 
  Eighteen 
  species 
  represent 
  the 
  Park 
  

   Mesozoic 
  flora 
  as 
  contained 
  in 
  the 
  Laramie 
  sandstones 
  of 
  the 
  Cre- 
  

   taceous, 
  no 
  plants 
  having 
  yet 
  been 
  found 
  from 
  the 
  Jura 
  or 
  Trias. 
  

  

  The 
  chief 
  points 
  of 
  geological 
  interest 
  arise 
  from 
  the 
  fact 
  that 
  

   all 
  the 
  Tertiary 
  plant 
  remains 
  occur 
  in 
  beds 
  of 
  volcanic 
  origin, 
  

   thus 
  giving 
  direct 
  evidence 
  of 
  the 
  age 
  and 
  period 
  of 
  some 
  of 
  the 
  

   great 
  igneous 
  activities 
  which 
  are 
  responsible 
  for 
  most 
  of 
  the 
  

   marvelous 
  geological 
  phenomena 
  of 
  this 
  region. 
  

  

  The 
  older 
  series 
  of 
  lavas, 
  as 
  determined 
  by 
  the 
  geologists, 
  have 
  

   been 
  designated 
  as 
  the 
  early 
  acid 
  breccias 
  and 
  flows, 
  while 
  the 
  

   younger 
  series 
  are 
  known 
  as 
  the 
  early 
  basic 
  breccias 
  and 
  flows. 
  

   Both 
  of 
  these 
  series 
  contain 
  ash 
  beds 
  probably 
  deposited 
  as 
  mud 
  

   flows. 
  In 
  these 
  the 
  plant 
  remains 
  have 
  been 
  preserved, 
  each 
  

   series 
  being 
  marked 
  by 
  different 
  floral 
  characteristics, 
  with 
  a 
  

   subordinate 
  intermediate 
  flora 
  in 
  the 
  upper 
  early 
  acid 
  breccias. 
  

  

  The 
  earliest 
  flora, 
  that 
  of 
  the 
  early 
  acid 
  breccias, 
  contains 
  

   seventy-nine 
  species, 
  of 
  which 
  forty-two 
  are 
  new 
  to 
  science. 
  Its 
  

   affinities 
  are 
  shown 
  to 
  be 
  with 
  those 
  of 
  the 
  Fort 
  Union 
  beds, 
  

   though 
  forms 
  common 
  to 
  the 
  Laramie, 
  Green 
  River, 
  and 
  Aurif- 
  

   erous 
  gravels 
  are 
  also 
  present. 
  The 
  intermediate 
  flora 
  is 
  related 
  

   to 
  that 
  of 
  the 
  younger 
  or 
  basic 
  series. 
  The 
  third 
  flora, 
  the 
  one 
  

   occurring 
  in 
  the 
  early 
  basic 
  breccias, 
  embraces 
  seventy 
  species, 
  

   and 
  is 
  shown 
  to 
  have 
  its 
  closest 
  relationships 
  with 
  the 
  Auriferous 
  

   gravels 
  of 
  California, 
  now 
  referred 
  to 
  the 
  Upper 
  Miocene 
  Ter- 
  

   tiary. 
  

  

  The 
  noted 
  fossil 
  forests 
  of 
  the 
  Yellowstone 
  National 
  Park 
  form 
  

   the 
  subject 
  of 
  a 
  separate 
  section. 
  They 
  are 
  undoubtedly 
  the 
  

  

  