﻿ANNIVERSARY 
  ADDRESS 
  OF 
  THE 
  PRESIDENT. 
  1 
  43 
  

  

  and 
  8 
  species 
  from 
  the 
  Middle 
  ; 
  and 
  2 
  genera 
  and 
  2 
  species 
  from 
  

   the 
  Upper 
  Lias. 
  Only 
  1 
  of 
  the 
  72 
  Lower 
  Lias 
  species 
  (Mont- 
  

   livaltia 
  excavata) 
  passes 
  to 
  the 
  Middle 
  Lias; 
  it 
  is 
  questionable 
  if 
  

   Lepidopliyllia 
  hebridensis 
  is 
  both 
  Lower 
  and 
  Upper 
  Lias; 
  and 
  I 
  

   even 
  doubt 
  if 
  Montlivaltia 
  excavata 
  above 
  mentioned 
  really 
  occurs 
  

   in 
  the 
  Middle 
  Lias 
  ; 
  should 
  this 
  be 
  so, 
  no 
  single 
  form 
  passes 
  from 
  

   the 
  Lower 
  Lias 
  to 
  higher 
  beds, 
  the 
  8 
  Middle 
  Lias 
  species 
  being 
  quite 
  

   distinct. 
  The 
  genera 
  represented 
  by 
  the 
  largest 
  number 
  of 
  species 
  

   are 
  Astrocoenia 
  (14 
  species), 
  Isastrcea 
  (7), 
  Montlivaltia 
  (20), 
  Sep- 
  

   tastrcea 
  (4), 
  and 
  Ihecosmilia 
  (14 
  species). 
  4 
  genera 
  are 
  recognized 
  

   by 
  a 
  single 
  species 
  each, 
  viz. 
  ? 
  Oyatliopliyllum 
  novum, 
  Lato- 
  

   mceandra 
  denticulata, 
  Oppelismilia 
  germinans, 
  and 
  Rliabdopliyllia 
  

   recondita 
  ; 
  Elyastraza 
  and 
  Tliecocyailius 
  have 
  only 
  2 
  representatives 
  

   each, 
  E. 
  Fischeri 
  and 
  E. 
  Moorei, 
  and 
  T. 
  rugosus 
  and 
  T. 
  Moorei 
  ; 
  I 
  

   name 
  these 
  because 
  of 
  their 
  rarity, 
  and 
  to 
  show 
  that 
  the 
  paucity 
  of 
  

   species 
  is 
  probably 
  due 
  to 
  want 
  of 
  research. 
  The 
  preponderance 
  of 
  

   species 
  in 
  the 
  genus 
  Montlivaltia 
  in 
  the 
  British 
  Jurassic 
  rocks 
  is 
  

   Greater 
  than 
  that 
  of 
  any 
  other 
  genus 
  of 
  corals 
  ; 
  no 
  less 
  than 
  43 
  

   species 
  are 
  known 
  ; 
  21 
  occur 
  in 
  the 
  Lower, 
  3 
  in 
  the 
  Middle, 
  and 
  

   1 
  in 
  the 
  Upper 
  Lias 
  ; 
  11 
  species 
  occur 
  in 
  the 
  Inferior 
  Oolite, 
  3 
  in 
  

   the 
  Puller's 
  earth, 
  3 
  in 
  the 
  Great 
  Oolite, 
  and 
  1 
  in 
  the 
  Coral 
  Eag 
  

   (M. 
  dispar). 
  Of 
  the 
  genus 
  Astrocoenia, 
  out 
  of 
  the 
  14 
  species 
  known, 
  

   no 
  less 
  than 
  13 
  belong 
  to 
  the 
  Lower 
  Lias 
  ; 
  and 
  Thecosmilia 
  is 
  in 
  

   much 
  the 
  same 
  case, 
  for 
  out 
  of 
  the 
  19 
  species 
  catalogued 
  14 
  are 
  also 
  

   Lower 
  Lias. 
  3 
  genera, 
  with 
  only 
  a 
  single 
  species 
  in 
  each, 
  occur 
  in 
  

   the 
  Middle 
  Lias 
  ; 
  and 
  I 
  believe 
  only 
  2 
  genera 
  and 
  2 
  species 
  are 
  

   known 
  in 
  the 
  Upper 
  Lias 
  ; 
  they 
  are 
  Montlivaltia 
  tubercidata 
  and 
  

   Trochocyathas 
  primus. 
  

  

  No 
  Actinozoa 
  (Aporosa) 
  occur 
  in 
  either 
  of 
  the 
  3 
  divisions 
  of 
  the 
  

   Lias 
  of 
  Yorkshire 
  ; 
  and 
  the 
  same 
  may 
  be 
  said 
  of 
  Dorsetshire. 
  There 
  

   scarcely 
  appears 
  any 
  physical 
  reason 
  why 
  such 
  should 
  be 
  the 
  case, 
  

   unless 
  the 
  Lias 
  of 
  the 
  north 
  and 
  south 
  of 
  England 
  was 
  accumulated 
  

   under 
  deep-sea 
  conditions 
  or 
  under 
  depression, 
  conditions 
  unsuitable 
  

   to 
  coral 
  growth 
  ; 
  whilst 
  the 
  more 
  central 
  portions 
  of 
  England, 
  now 
  

   Warwickshire, 
  Oxfordshire, 
  Northamptonshire, 
  &c, 
  were 
  probably 
  

   risin<>- 
  or 
  stationary, 
  giving 
  time 
  for 
  the 
  coral 
  fauna 
  to 
  be 
  developed. 
  

   Certainly 
  most 
  of 
  the 
  Lower 
  and 
  Middle 
  series 
  of 
  the 
  Jurassic 
  rocks 
  

   were 
  deposited 
  in 
  moderately 
  shallow 
  water. 
  In 
  Yorkshire, 
  from 
  

   the 
  Doo-o-er 
  upwards 
  to 
  the 
  Kellaways 
  Eock, 
  or 
  the 
  base 
  of 
  the 
  Ox- 
  

   fordian 
  °roup, 
  this 
  was 
  certainly 
  the 
  case 
  ; 
  and 
  in 
  Northamptonshire 
  

   the 
  same. 
  All 
  the 
  Jurassic 
  rocks 
  of 
  Yorkshire 
  only 
  yield 
  12 
  species, 
  

   .3 
  in 
  the 
  Lower 
  and 
  9 
  in 
  the 
  Middle 
  Oolite. 
  

  

  Middle 
  Lias. 
  — 
  Astrocoenia 
  Oppelii, 
  Cyclolites 
  cupidiformis, 
  Lepi- 
  

   donluilUa 
  hebridensis, 
  Montlivaltia 
  foliacea, 
  M. 
  Victoria, 
  M. 
  excavata, 
  

   Thamnastrcea 
  Etlieridgii, 
  and 
  Tricycloseris 
  Anninigim 
  are 
  the 
  only 
  

   Actinozoa 
  known 
  in 
  the 
  Middle 
  Lias 
  ; 
  their 
  geographical 
  distribu- 
  

   tion 
  is 
  as 
  varied 
  as 
  the 
  species 
  are 
  few. 
  The 
  following 
  Table 
  

   (XVIII.) 
  will 
  show 
  their 
  distribution 
  : 
  — 
  

  

  