﻿Geology 
  and 
  Mineralogy. 
  475 
  

  

  their 
  filiation 
  is 
  an 
  established 
  hypothesis. 
  It 
  is 
  also 
  a 
  curious 
  

   fact 
  that 
  these 
  two 
  species 
  or 
  varieties 
  are 
  brusquely 
  produced 
  at 
  

   the 
  same 
  time 
  throughout 
  the 
  whole 
  basin, 
  that 
  they 
  are 
  preceded 
  

   by 
  no 
  attempt 
  of 
  the 
  species 
  to 
  acquire 
  these 
  new 
  forms, 
  that 
  

   they 
  arose 
  when 
  Spirifer 
  vemeuili 
  had 
  not 
  yet 
  reached 
  any 
  

   important 
  variation, 
  and 
  possessed 
  all 
  its 
  primitive 
  uniformity, 
  

   that 
  they 
  disappear 
  finally 
  very 
  rapidly 
  and 
  brusquely 
  as 
  they 
  

   arose, 
  and 
  that 
  their 
  descendants, 
  if 
  they 
  are 
  not 
  lost, 
  returned 
  to 
  

   the 
  general 
  type 
  of 
  the 
  species 
  vemeuili. 
  

  

  As 
  to 
  the 
  Spirifer 
  called 
  bifidus, 
  if 
  it 
  possessed 
  some 
  forms 
  

   which 
  may 
  be 
  compared 
  with 
  vemeuili, 
  it 
  differs 
  from 
  it 
  by 
  an 
  

   essential 
  character 
  which 
  it 
  manifests 
  even 
  in 
  its 
  young 
  age. 
  It 
  

   should 
  also 
  be 
  borne 
  " 
  in 
  mind 
  that 
  the 
  forms 
  of 
  passage, 
  of 
  

   doubtful 
  determination, 
  were 
  produced 
  only 
  when 
  the 
  true 
  

   Spirifer 
  bifidus 
  of 
  the 
  Frasnien 
  limestone 
  was 
  departing 
  from 
  the 
  

   geological 
  arena, 
  at 
  least 
  in 
  the 
  Ardenne;" 
  p. 
  61. 
  

  

  The 
  methods 
  employed 
  in 
  this 
  investigation 
  and 
  the 
  results 
  

   obtained 
  will 
  suggest 
  to 
  the 
  thoughtful 
  paleontologist 
  problems 
  

   of 
  the 
  deepest 
  interest 
  and 
  promising 
  rich 
  reward 
  to 
  those 
  who 
  

   will 
  thoroughly 
  investigate 
  them^YAy^^^^y^ 
  h. 
  s. 
  w. 
  

  

  3. 
  Geological 
  /Survey 
  nf^B&ma^^ 
  vol. 
  iv, 
  Paleontology 
  of 
  

   Parts 
  I 
  and 
  II, 
  by 
  Chas. 
  R. 
  Keyes, 
  State 
  Geologist, 
  pp. 
  

  

  1-271, 
  plates 
  xii-xxxii, 
  colored 
  geological 
  map 
  of 
  the 
  state, 
  scale 
  

   1 
  in. 
  to 
  18 
  miles, 
  and 
  pp. 
  1-266, 
  plates 
  xxxiii-lvi. 
  Jefferson 
  City, 
  

   Mo. 
  1894. 
  — 
  This 
  is 
  a 
  valuable 
  contribution 
  to 
  the 
  Paleontological 
  

   literature 
  of 
  the 
  Mississippi 
  valley 
  formations, 
  giving 
  as 
  it 
  does 
  a 
  

   carefully 
  compiled 
  list 
  of 
  the 
  already 
  described 
  invertebrate 
  

   forms 
  of 
  the 
  rocks 
  of 
  Missouri, 
  with 
  descriptions 
  of 
  many, 
  full 
  

   references 
  to 
  synonomy 
  in 
  most 
  cases, 
  and 
  illustration 
  of 
  many 
  

   already 
  figured 
  forms 
  and 
  of 
  several 
  new 
  species. 
  We 
  regret 
  to 
  

   note 
  that 
  there 
  are 
  still 
  numerous 
  species 
  named 
  and 
  described 
  by 
  

   Swallow 
  but 
  without 
  figures, 
  which 
  the 
  author 
  of 
  this 
  work 
  still 
  

   leaves 
  unfigured. 
  If 
  he, 
  having 
  access 
  to 
  the 
  type 
  collections, 
  is 
  

   unable 
  to 
  furnish 
  typical 
  figures, 
  it 
  is 
  time 
  to 
  discard 
  from 
  

   synonomy 
  such 
  unidentifyable 
  references. 
  

  

  In 
  the 
  early 
  part 
  of 
  the 
  first 
  volume 
  on 
  the 
  geological 
  forma- 
  

   tions 
  the 
  author 
  proposes 
  to 
  substitute 
  another 
  name 
  for 
  the 
  

   Osage 
  group 
  which 
  for 
  several 
  years 
  has 
  been 
  in 
  use 
  to 
  indicate 
  

   the 
  general 
  formation 
  which 
  locally 
  has 
  been 
  called 
  Burlington 
  

   and 
  Keokuk 
  limestone 
  on 
  account 
  of 
  the 
  continuous 
  fauna 
  which 
  

   appears 
  to 
  characterize 
  them. 
  The 
  argument, 
  that 
  because 
  there 
  

   has 
  been 
  found 
  a 
  more 
  complete 
  section 
  near 
  Augusta, 
  Iowa, 
  

   than 
  in 
  the 
  region 
  through 
  which 
  the 
  Osage 
  river 
  flows, 
  the 
  first 
  

   name 
  may 
  therefore 
  be 
  discarded, 
  is 
  quite 
  contrary 
  to 
  the 
  general 
  

   principle 
  of 
  priority 
  in 
  the 
  application 
  of 
  scientific 
  names. 
  So 
  

   long 
  as 
  the 
  meaning 
  is 
  accepted, 
  understood 
  and 
  applicable 
  in 
  

   the 
  region 
  from 
  which 
  the 
  name 
  was 
  derived, 
  the 
  Osage 
  group 
  

   has 
  the 
  priority. 
  h. 
  s. 
  w. 
  

  

  4. 
  Geological 
  Survey 
  of 
  New 
  Jersey 
  : 
  Ann. 
  JRept. 
  of 
  the 
  State 
  

   Geologist 
  for 
  1894, 
  pp. 
  1-457 
  with 
  five 
  maps, 
  plates 
  i-x, 
  figures 
  

  

  