﻿ANNIVERSARY 
  ADDRESS 
  OF 
  THE 
  PRESIDENT. 
  185 
  

  

  cies 
  to 
  each 
  of 
  8 
  genera 
  — 
  Triyonia 
  costata, 
  Quenstedtia 
  laevigata, 
  My- 
  

   opsis 
  jurassii^.), 
  Modiola 
  imbricata, 
  Goniomya 
  v-scripta, 
  Anatina 
  

   undulata, 
  Area 
  osmula, 
  and 
  Astarte 
  excavata. 
  

  

  The 
  Bivalves 
  of 
  the 
  Inferior 
  Oolite, 
  numbering 
  (52 
  genera 
  and 
  

   342 
  species, 
  and 
  from 
  which 
  the 
  higher 
  horizons 
  have 
  been 
  sup- 
  

   plied 
  through 
  either 
  direct 
  descent 
  or 
  evolution, 
  cannot 
  receive 
  too 
  

   much 
  attention; 
  the 
  fact 
  that 
  only 
  f 
  9 
  Monomyarian 
  forms 
  and 
  \\ 
  

   Dimyarian 
  come 
  from 
  the 
  Lias 
  below 
  (so 
  far 
  as 
  we 
  know) 
  renders 
  

   this 
  division 
  of 
  the 
  Lower 
  Oolite 
  of 
  interest. 
  

  

  Gasteropoda. 
  — 
  The 
  whole 
  of 
  the 
  Jurassic 
  Gasteropoda 
  number 
  

   76 
  genera 
  and 
  1015 
  species 
  ; 
  and 
  those 
  of 
  the 
  Inferior 
  Oolite 
  41 
  

   genera 
  and 
  240 
  species. 
  The 
  Lias 
  group 
  holds 
  51 
  genera 
  and 
  388 
  

   species 
  ( 
  2 
  4 
  2 
  \ 
  in 
  the 
  Lower, 
  ^.J 
  Q 
  in 
  the 
  Middle, 
  and 
  1 
  § 
  in 
  the 
  Upper 
  

   Lias) 
  ; 
  and 
  now 
  we 
  find 
  that, 
  with 
  the 
  passage 
  of 
  only 
  ^ 
  genera 
  

   and 
  species 
  to 
  the 
  Inferior 
  Oolite, 
  a 
  totally 
  new 
  Gasteropod 
  fauna, 
  

   numbering 
  240, 
  occurs 
  : 
  and, 
  beyond 
  the 
  fact 
  that 
  22 
  genera 
  and 
  

   40 
  species 
  are 
  common 
  to 
  it 
  and 
  the 
  Great 
  Oolite, 
  the 
  species 
  are 
  

   almost 
  confined 
  to 
  the 
  horizon 
  of 
  the 
  inferior 
  division. 
  Only 
  one 
  

   species 
  {Maria 
  Phillipsii) 
  seems 
  to 
  unite 
  the 
  Fullers 
  Earth 
  with 
  

   the 
  Inferior 
  Oolite 
  ; 
  no 
  other 
  species 
  has 
  been 
  found, 
  although 
  in 
  

   the 
  Fulier's-earth 
  rock 
  we 
  should 
  expect 
  to 
  meet 
  with 
  forms 
  that 
  

   pass 
  over 
  and 
  appear 
  in 
  the 
  Great 
  Oolite, 
  of 
  which 
  (as 
  stated) 
  there 
  

   are 
  \ 
  § 
  species. 
  The 
  largely 
  represented 
  genera 
  are 
  

  

  Alaria 
  19 
  species. 
  

  

  Cerithium 
  10 
  „ 
  

  

  Chemnitzia 
  .... 
  9 
  „ 
  

  

  Nerinaea 
  12 
  „ 
  

  

  Pleurotomaria 
  . 
  . 
  47 
  ,, 
  

  

  Trochus 
  20 
  „ 
  

  

  Turbo 
  17 
  „ 
  

  

  The 
  rarer 
  genera 
  are 
  sparingly 
  represented 
  — 
  JBidla, 
  Ceritella, 
  Cirrus, 
  

   Crossostoma, 
  Fissurella, 
  Melania, 
  Ouustus, 
  Pileolus, 
  Pterocera, 
  Sca- 
  

   laria, 
  Solarium, 
  and 
  Bpiniyera 
  by 
  one 
  or 
  two 
  species 
  each. 
  G 
  genera 
  

   and 
  7 
  species 
  pass 
  to 
  the 
  Forest 
  Marble, 
  and 
  4 
  genera 
  and 
  6 
  species 
  

   to 
  the 
  Cornbrash. 
  The 
  22 
  genera 
  and 
  40 
  species 
  believed 
  to 
  occur 
  

   in 
  both 
  the 
  Inferior 
  and 
  Great 
  Oolite 
  may 
  be 
  in 
  excess 
  of 
  the 
  

   truth 
  ; 
  the 
  species 
  in 
  Morris 
  and 
  Lycett's 
  memoir 
  on 
  the 
  Mollusca 
  

   of 
  the 
  Great 
  Oolite 
  (Pal. 
  Soc.) 
  have 
  often 
  had 
  Inferior- 
  Oolite 
  forms 
  

   referred 
  to 
  them, 
  which 
  would 
  not 
  have 
  been 
  done 
  had 
  we 
  an 
  equally 
  

   reliable 
  monograph 
  upon 
  the 
  Mollusca 
  of 
  the 
  Inferior 
  Oolite. 
  The 
  

   \ 
  I 
  genera 
  and 
  species 
  are 
  mostly 
  among 
  the 
  larger 
  genera 
  ; 
  yet, 
  after 
  

   all, 
  it 
  is 
  comparatively 
  a 
  small 
  number, 
  not 
  one 
  genus 
  in 
  four, 
  or 
  one 
  

   species 
  in 
  ten 
  of 
  the 
  whole 
  univalve 
  fauna. 
  Only 
  ij 
  pass 
  to 
  the 
  Kella- 
  

   ways 
  Rock, 
  viz. 
  Pleurotomaria 
  yramdata,NaticapuRctura, 
  and 
  Alaria 
  

   trijida. 
  This 
  last 
  is 
  the 
  only 
  species 
  that 
  passes 
  to 
  the 
  Oxford 
  Clay 
  ; 
  

   and 
  Turbo 
  funieulatus 
  is 
  the 
  only 
  known 
  univalve 
  shell 
  common 
  to 
  the 
  

   Coral 
  Rag 
  and 
  Inferior 
  Oolite. 
  But 
  for 
  the 
  researches 
  of 
  Dr. 
  Lycett 
  

   in 
  the 
  rich 
  district 
  of 
  Minchinhampton, 
  little 
  or 
  nothing 
  would 
  have 
  

  

  