﻿Report 
  oi 
  the 
  State 
  Geologist. 
  913 
  

  

  From 
  a 
  reference 
  to 
  the 
  figures 
  illustrating 
  Phyllopora 
  

   Ehrenbergi, 
  the 
  typical 
  species, 
  it 
  will 
  be 
  seen 
  that 
  this 
  descrip- 
  

   tion 
  is 
  somewhat 
  misleading. 
  The 
  figures 
  show 
  that 
  the 
  general 
  

   appearance 
  of 
  the 
  genus 
  is 
  the 
  same 
  as 
  that 
  of 
  an 
  infundibuli- 
  

   f 
  orm 
  frond 
  of 
  Fenestella 
  with 
  wide 
  dissepiments 
  and 
  differs 
  from 
  

   an 
  uncarinated 
  Fenestella 
  in 
  having 
  apertures 
  on 
  the 
  dissepi- 
  

   ments 
  as 
  well 
  as 
  the 
  branches. 
  

  

  In 
  every 
  case 
  where 
  a 
  diagnosis 
  differs 
  from 
  the 
  illustrations 
  I 
  

   have 
  unhesitatingly 
  accepted 
  the 
  illustrations 
  as 
  authority 
  in 
  

   preference 
  to 
  the 
  description, 
  for 
  it 
  is 
  almost 
  impossible 
  to 
  describe 
  

   the 
  peculiarities 
  of 
  a 
  genus 
  so 
  that 
  its 
  form 
  is 
  correctly 
  reproduced 
  

   in 
  the 
  mind 
  of 
  another 
  ; 
  and 
  with 
  the 
  multiplication 
  of 
  genera 
  

   and 
  species 
  this 
  becomes 
  more 
  and 
  more 
  difficult, 
  while 
  the 
  

   different 
  shades 
  of 
  meaning 
  attached 
  by 
  different 
  persons 
  to 
  the 
  

   same 
  words 
  and 
  phrases 
  renders 
  a 
  description 
  without 
  illustrations 
  

   practically 
  useless. 
  Also 
  one 
  may 
  derive 
  an 
  entirely 
  incorrect 
  

   conclusion 
  from 
  what 
  he 
  observes, 
  and 
  the 
  various 
  parts 
  

   of 
  an 
  organism 
  may 
  seem 
  to 
  him 
  to 
  serve 
  a 
  purpose 
  entirely 
  

   different 
  from 
  their 
  real 
  use 
  ; 
  but 
  having 
  a 
  correct 
  drawing 
  of 
  

   an 
  object 
  before 
  us 
  is 
  the 
  same 
  as 
  if 
  we 
  had 
  the 
  object 
  itself, 
  and 
  

   we 
  can 
  not 
  be 
  misled 
  by 
  inaccuracies 
  in 
  the 
  description. 
  

  

  Holding 
  these 
  views 
  I 
  am 
  pleased 
  to 
  find 
  the 
  following 
  

   passage 
  in 
  British 
  Fossil 
  Brachiopoda 
  by 
  Davidson, 
  who 
  is 
  

   without 
  a 
  rival 
  in 
  the 
  clearness 
  of 
  his 
  descriptions: 
  "In 
  1852 
  in 
  

   the 
  second 
  fasciculus 
  of 
  his 
  important 
  work, 
  ' 
  British 
  Palaeozoic 
  

   Fossils,' 
  Prof. 
  McCoy 
  described 
  with 
  great 
  minuteness 
  118 
  

   species 
  or 
  varieties 
  of 
  British 
  Palaeozoic 
  Brachiopoda, 
  but 
  of 
  

   these 
  he 
  figures 
  only 
  twenty-five. 
  It 
  is 
  much 
  to 
  be 
  regretted 
  

   that 
  a 
  larger 
  number 
  of 
  the 
  fossils 
  had 
  not 
  been 
  illustrated, 
  

   for 
  a 
  good 
  figure 
  is 
  often 
  more 
  valuable 
  than 
  the 
  most 
  elabor- 
  

   ate 
  description, 
  and 
  especially 
  so 
  when 
  forms 
  vary 
  so 
  slightly 
  

   from 
  one 
  another 
  that 
  at 
  times 
  it 
  is 
  hardly 
  possible 
  to 
  adequately 
  

   express 
  with 
  words 
  small 
  differences 
  which 
  the 
  figure 
  at 
  once 
  

   conveys 
  to 
  the 
  eye 
  of 
  the 
  experienced 
  observer." 
  Beale, 
  in 
  

   " 
  How 
  to 
  Work 
  With 
  the 
  Microscope," 
  says 
  : 
  We 
  may 
  reasonably 
  

   hope 
  that 
  those 
  who 
  follow 
  us 
  will 
  look 
  at 
  our 
  drawings, 
  if 
  

   we 
  are 
  careful 
  to 
  make 
  honest 
  copies 
  of 
  nature, 
  but 
  we 
  can 
  

   hardly 
  expect 
  that 
  much 
  of 
  which 
  is 
  now 
  written 
  will 
  be 
  read 
  

   some 
  years 
  hence, 
  when 
  the 
  whole 
  aspect 
  of 
  the 
  department 
  

   of 
  science 
  we 
  love 
  to 
  develop 
  will 
  be 
  completely 
  changed. 
  

   115 
  

  

  