﻿T. 
  DAVIDSON 
  AND 
  W. 
  KING 
  ON 
  THE 
  TRIMERELLID^E. 
  173 
  

  

  life. 
  It 
  would 
  be 
  well 
  worth 
  while 
  to 
  follow 
  the 
  inquiry 
  how 
  far 
  

   they 
  were 
  related. 
  

  

  Prof. 
  Ramsay 
  was 
  delighted 
  to 
  hear 
  the 
  opinion 
  expressed 
  by 
  

   Mr. 
  Davidson, 
  that 
  the 
  distinction 
  of 
  species 
  was 
  merely 
  an 
  abstract 
  

   idea. 
  He 
  had 
  always 
  considered 
  that 
  the 
  apparent 
  distinction 
  of 
  

   species 
  was 
  due 
  to 
  the 
  absence 
  of 
  the 
  connecting 
  links. 
  He 
  was 
  

   thankful 
  to 
  Mr. 
  Davidson 
  for 
  stating 
  that 
  in 
  different 
  geological 
  

   formations 
  there 
  were 
  forms 
  which 
  had 
  received 
  distinct 
  specific 
  

   names 
  but 
  which 
  he 
  could 
  not 
  distinguish 
  otherwise 
  than 
  by 
  their 
  

   derivation. 
  Mr. 
  Hicks 
  had 
  spoken 
  of 
  the 
  three 
  forms 
  of 
  organisms 
  

   which 
  occur 
  deep 
  down 
  in 
  the 
  Cambrian, 
  and 
  founded 
  an 
  argument 
  

   upon 
  their 
  rarity. 
  But 
  Prof. 
  Eamsay 
  had 
  long 
  maintained 
  the 
  

   heterodox 
  opinion 
  that 
  the 
  Lower 
  Cambrian 
  was 
  a 
  freshwater 
  for- 
  

   mation, 
  in 
  which 
  marine 
  deposits 
  are 
  here 
  and 
  there 
  intercalated. 
  

   He 
  looked 
  forward 
  to 
  the 
  future 
  discovery 
  of 
  marine 
  Lower 
  Cam- 
  

   brian 
  beds 
  with 
  a 
  much 
  richer 
  fauna, 
  and 
  considered 
  that 
  it 
  was 
  

   only 
  from 
  accidental 
  circumstances 
  that 
  the 
  fauna 
  of 
  the 
  Lower 
  

   Cambrian 
  is 
  so 
  poor. 
  

  

  Mr. 
  Etheridge 
  also 
  called 
  attention 
  to 
  the 
  poverty 
  of 
  the 
  Lower 
  

   Cambrian 
  fauna 
  in 
  Great 
  Britain. 
  

  

  Mr. 
  Boyd 
  Dawkins 
  remarked 
  that 
  the 
  most 
  lowly 
  organized 
  forms 
  

   seemed 
  to 
  be 
  the 
  most 
  persistent. 
  

  

  Q.J. 
  G. 
  S. 
  No. 
  118. 
  

  

  