﻿FOURTH 
  REPORT 
  OF 
  THE 
  DIRECTOR 
  I907 
  1 
  67 
  

  

  Fistulipora 
  occidens 
  presents 
  a 
  similar 
  coalition 
  of 
  a 
  

   hydroid 
  coral 
  and 
  the 
  primitive 
  tubulate 
  Aulopora. 
  This 
  species 
  

   was 
  described 
  from 
  the 
  Upper 
  Devonic 
  Lime 
  Creek 
  shales 
  of 
  Rock- 
  

   ford, 
  Iowa, 
  by 
  Hall 
  [N. 
  Y. 
  State 
  Mus. 
  23d 
  Rep't. 
  1873. 
  P- 
  228 
  > 
  

   pi. 
  10, 
  p. 
  9, 
  10] 
  who 
  recognized 
  the 
  fact 
  that 
  the 
  large 
  pores 
  on 
  

   the 
  surface 
  of 
  the 
  coral 
  are 
  projecting 
  tubes 
  of 
  Aulopora. 
  An 
  in- 
  

   teresting 
  feature 
  of 
  this 
  concurrence 
  is 
  that 
  colonies 
  of 
  the 
  Fistuli- 
  

   pora 
  are 
  quite 
  as 
  frequently 
  without 
  the 
  Aulopora 
  as 
  with 
  it. 
  

  

  One 
  may 
  compare 
  with 
  these 
  instances 
  the 
  interesting 
  case 
  

   mentioned 
  by 
  Whitfield 
  of 
  the 
  recent 
  coral 
  Ctenophyllia, 
  entirely 
  

   inclosed 
  by 
  a 
  hemispherical 
  growth 
  of 
  Meandrina 
  labyrin- 
  

   thica 
  (described 
  in 
  Am. 
  Mus. 
  Nat. 
  Hist. 
  Bui. 
  1901. 
  14: 
  221). 
  

  

  In 
  addition 
  to 
  the 
  instances 
  given 
  above 
  of 
  actual 
  commensal 
  

   conditions, 
  I 
  am 
  taking 
  this 
  occasion 
  to 
  append 
  a 
  brief 
  account 
  of 
  

   certain 
  ancient 
  pseudoparasitic 
  organisms 
  of 
  boring 
  habit. 
  These 
  

   come 
  frequently 
  under 
  the 
  eye 
  of 
  the 
  paleontologist 
  but 
  very 
  little 
  

   attention 
  has 
  been 
  given 
  to 
  them, 
  occasional 
  incidental 
  references 
  

   being 
  for 
  the 
  most 
  part 
  the 
  sum 
  of 
  our 
  knowledge 
  of 
  the 
  Paleozoic 
  

   expressions. 
  The 
  literature 
  of 
  the 
  later 
  formations 
  contains 
  random 
  

   accounts 
  of 
  such 
  organic 
  relics 
  but 
  I 
  should 
  be 
  going 
  too 
  far 
  afield 
  

   in 
  this 
  instance 
  to 
  make 
  definite 
  allusion 
  to 
  these. 
  1 
  

  

  These 
  boring 
  bodies 
  infesting 
  the 
  dead 
  shells 
  which 
  form 
  a 
  large 
  

   part 
  of 
  the 
  material 
  of 
  the 
  paleontologist 
  are 
  very 
  likely 
  to 
  be 
  either 
  

   minute 
  algae 
  or 
  fungi, 
  or 
  sponges 
  of 
  genera 
  producing 
  similar 
  effects 
  

   to 
  the 
  living 
  Cliona 
  or 
  Vioa. 
  The 
  work 
  of 
  the 
  former 
  has 
  had 
  some 
  

   notice 
  [see 
  Duncan 
  Quar. 
  Jour. 
  Geol. 
  Soc. 
  1876. 
  p. 
  205; 
  Kolliker. 
  

   Zeitschr. 
  Wiss. 
  Zoolog. 
  1859, 
  10: 
  215; 
  Loomis, 
  N. 
  Y. 
  State 
  Mus. 
  

   Bui. 
  39. 
  1900. 
  p. 
  223] 
  and 
  their 
  tubules 
  are 
  recognizable 
  by 
  contrast 
  

   by 
  their 
  microscopic 
  size 
  and 
  the 
  occasional 
  presence 
  of 
  hyphal 
  

   swellings. 
  The 
  total 
  amount 
  of 
  deterioration 
  and 
  disintegration 
  

   of 
  skeletons 
  caused 
  by 
  these 
  minute 
  organisms 
  was 
  doubtless 
  

   great 
  even 
  in 
  Paleozoic 
  times. 
  

  

  The 
  work 
  of 
  boring 
  sponges, 
  however, 
  on 
  ancient 
  organisms 
  has 
  

   been 
  a 
  far 
  more 
  effective 
  cause 
  of 
  destruction 
  and 
  waste 
  of 
  dead 
  

   shells. 
  There 
  are 
  certain 
  conditions 
  of 
  preservation 
  in 
  which 
  these 
  

   borings 
  enforce 
  themselves 
  on 
  the 
  attention, 
  especially 
  when 
  the 
  

   student 
  has 
  to 
  deal 
  with 
  an 
  arenaceous 
  matrix 
  from 
  which 
  all 
  the 
  

   calcareous 
  matter 
  of 
  the 
  shells 
  has 
  been 
  dissolved 
  leaving 
  sharp 
  

  

  H'ery 
  instructive 
  instances 
  of 
  these 
  later 
  expressions 
  are 
  cited 
  in 
  a 
  recent 
  paper 
  by 
  E. 
  

   Scbiitze, 
  Die 
  bohrenden 
  und 
  schmarotzenden 
  Fossilien 
  der 
  schwMbischen 
  Meeresmolasse, 
  

   Jahresb. 
  d.Ver. 
  f. 
  vaterl. 
  Naturk. 
  in 
  Wiirtt. 
  63, 
  1907. 
  p. 
  81-84; 
  Bericht 
  ueb. 
  29Versamml. 
  

   d. 
  Oberrhein. 
  geolog. 
  Vereins 
  zu 
  Worth, 
  1906; 
  Zeitschr. 
  f. 
  Mineral. 
  Geol. 
  u. 
  Palaeont. 
  

   Jahrg. 
  1. 
  

  

  