﻿I5 
  2 
  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  attached 
  condition 
  among 
  organisms 
  involves 
  and 
  expresses 
  degen- 
  

   eration 
  and 
  necessarily 
  promulgates 
  still 
  further 
  decline, 
  biologists 
  

   are 
  well 
  agreed. 
  1 
  An 
  argument 
  therefore 
  to 
  show 
  that 
  groups 
  of 
  

   attached 
  organisms 
  like 
  the 
  corals, 
  the 
  sponges, 
  the 
  bryozoans, 
  

   are 
  degenerate 
  and 
  that 
  their 
  apparent 
  simplicity 
  of 
  structure 
  is 
  

   less 
  a 
  primitive 
  than 
  a 
  derived 
  condition, 
  is 
  not 
  here 
  called 
  for. 
  

  

  As 
  we 
  contemplate 
  the 
  earliest 
  faunas 
  of 
  the 
  earth 
  we 
  find 
  

   that 
  adherent 
  and 
  attached 
  forms 
  of 
  life 
  are 
  in 
  a 
  notably 
  less 
  

   proportion 
  than 
  in 
  the 
  faunas 
  succeeding. 
  Bryozoans, 
  crinoids, 
  

   corals, 
  sponges, 
  attached 
  worms 
  are 
  extremely 
  rare; 
  trilobites 
  and 
  

   brachiopods 
  enormously 
  predominate. 
  The 
  trilobites 
  were 
  crawlers 
  

   and 
  swimmers. 
  The 
  brachiopods 
  however 
  were 
  of 
  different 
  habit. 
  

   The 
  predominating 
  forms 
  were 
  the 
  inarticulate 
  species 
  allied 
  in 
  

   structure 
  to 
  the 
  living 
  Lingula 
  and, 
  if 
  allied 
  also 
  in 
  habit, 
  

   burrowed 
  in 
  the 
  mud 
  of 
  the 
  sea 
  bottom 
  with 
  their 
  fleshy 
  pedicles, 
  

   potentially 
  not 
  actually 
  attached. 
  Some 
  of 
  the 
  genera 
  with 
  long 
  

   pedicle 
  sheaths 
  may 
  not 
  have 
  had 
  this 
  habit 
  but 
  have 
  been 
  actually 
  

   attached 
  to 
  solid 
  objects 
  by 
  their 
  arm; 
  this 
  was 
  undoubtedly 
  the 
  

   habit 
  of 
  the 
  articulate 
  brachiopods 
  also 
  until 
  the 
  time 
  came 
  with 
  

   the 
  maturity 
  of 
  these 
  creatures 
  when 
  the 
  arm 
  was 
  atrophied 
  and 
  

   they 
  fell 
  back 
  on 
  the 
  sea 
  bottom, 
  free 
  but 
  still 
  incapable 
  of 
  loco- 
  

   motion. 
  In 
  this 
  condition, 
  like 
  many 
  bivalves 
  (e. 
  g. 
  Mya, 
  the 
  soft- 
  

   shelled 
  clam, 
  which 
  lies 
  buried 
  in 
  the 
  mud 
  with 
  no 
  power- 
  to 
  get 
  

   any 
  way' 
  but 
  further 
  in) 
  they 
  were 
  potentially 
  attached 
  though 
  

   actually 
  independent. 
  

  

  To 
  the 
  faunas 
  earlier 
  than 
  the 
  Cambric 
  with 
  their 
  probable 
  

   decrease 
  of 
  attached 
  organisms, 
  we 
  can 
  not 
  appeal. 
  We 
  can, 
  

   however, 
  still 
  follow 
  the 
  line 
  of 
  our 
  argument 
  into 
  those 
  earlier 
  faunas 
  

   which 
  still 
  remain 
  unrevealed. 
  

  

  In 
  all 
  shell 
  bearing 
  organisms 
  the 
  shell 
  is 
  not 
  a 
  primitive 
  but 
  a 
  

   secondary 
  development. 
  Primitive 
  organisms, 
  as 
  all 
  considera- 
  

   tions 
  of 
  biology 
  insist, 
  were 
  shell-less 
  throughout 
  their 
  existence 
  — 
  a 
  

   conclusion 
  not 
  only 
  indicated 
  by 
  ontogeny 
  but 
  by 
  philosophy. 
  The 
  

   generally 
  accepted 
  conception 
  that 
  the 
  archetype 
  of 
  organic 
  life 
  was 
  

   a 
  naked 
  free-swimming 
  pelagic 
  creature 
  may 
  be 
  supplemented 
  by 
  the 
  

   proposition 
  that 
  the 
  primitive 
  condition 
  of 
  all 
  organisms 
  even, 
  after 
  

   departure 
  from 
  the 
  radicle 
  was 
  still 
  naked 
  and 
  free. 
  We 
  must 
  con- 
  

   ceive 
  that 
  only 
  as 
  the 
  independent 
  soft 
  -bodied 
  animals 
  of 
  the 
  earliest 
  

  

  J 
  See 
  especially 
  Arnold 
  Lang. 
  Einfluss 
  der 
  festsUzenden 
  Lebensweise. 
  

  

  