﻿ANNIVERSARY 
  ADDRESS 
  OF 
  THE 
  PRESIDENT. 
  

  

  139 
  

  

  wick, 
  Hildesheini 
  and 
  Hanover. 
  The 
  Yaudois 
  Alps, 
  the 
  Canton 
  of 
  

   Aargau, 
  and 
  near 
  Basel 
  arc 
  localities 
  in 
  Switzerland. 
  

  

  The 
  Cote 
  d'Or, 
  Aveyron, 
  Herault, 
  Luxembourg, 
  and 
  Belgium 
  

   possess 
  this 
  transition 
  group 
  in 
  greater 
  or 
  less 
  development 
  ; 
  it 
  

   varies 
  in 
  thickness 
  from 
  40 
  to 
  3000 
  feet 
  throughout 
  its 
  distribution 
  

   in 
  Spain. 
  The 
  most 
  complete 
  sections 
  in 
  England 
  are 
  to 
  be 
  studied 
  

   at 
  Aust 
  Passage 
  and 
  Garden 
  Cliff, 
  Westbury 
  (Gloucestershire), 
  Pe- 
  

   narth 
  Cliff 
  (Glamorganshire), 
  and 
  St. 
  Audrey's 
  slip 
  (Somersetshire) 
  ; 
  

   nowhere 
  do 
  they 
  exceed 
  50 
  feet 
  in 
  thickness, 
  but 
  lithologically 
  and 
  

   palaeontologically 
  they 
  are 
  the 
  same 
  throughout. 
  

  

  It 
  is 
  difficult 
  to 
  arrive 
  at 
  the 
  true 
  number 
  of 
  species 
  in 
  the 
  Rhaetic 
  

   zones 
  of 
  Britain 
  ; 
  they 
  are 
  a 
  group 
  not 
  easily 
  studied 
  and 
  difficult 
  to 
  

   obtain. 
  Our 
  knowledge 
  of 
  the 
  fauna 
  is 
  incomplete, 
  owing 
  to 
  the 
  

   physical 
  structure 
  or 
  fissile 
  and 
  shaly 
  nature 
  of 
  the 
  beds, 
  no 
  

   limestone 
  of 
  appreciable 
  and 
  constant 
  thickness 
  occurring 
  in 
  the 
  

   series 
  ; 
  as 
  near 
  as 
  I 
  can 
  tell, 
  we 
  possess 
  54 
  genera 
  and 
  100 
  species, 
  

   which 
  mav 
  be 
  tabulated 
  as 
  follows 
  : 
  — 
  

  

  

  Genera. 
  

  

  Species. 
  

  

  Plantae 
  

  

  2 
  or 
  3 
  

  

  3 
  

  

  Asteroidea 
  . 
  . 
  . 
  

  

  1 
  

  

  1 
  

  

  Crustacea 
  . 
  . 
  . 
  

  

  3 
  

  

  3 
  

  

  Brachiopoda 
  . 
  

  

  1 
  

  

  1 
  

  

  Monomyaria 
  . 
  

  

  9 
  

  

  15 
  

  

  Dimyaria 
  . 
  . 
  

  

  13 
  

  

  25 
  

  

  Gasteropoda 
  . 
  

  

  8 
  

  

  17 
  

  

  Cephalopoda 
  . 
  

  

  none 
  

  

  none 
  

  

  Pisces 
  

  

  12 
  

  

  27* 
  

  

  Reptilia 
  

  

  2 
  

  

  4 
  

  

  Mammalia 
  . 
  . 
  . 
  

  

  2 
  

  

  4 
  

  

  54 
  

  

  100 
  

  

  In 
  the 
  famous 
  sections 
  of 
  Aust 
  Passage, 
  Westbury 
  or 
  Garden 
  

   Cliff, 
  Wainlode, 
  &c, 
  fifty 
  species 
  have 
  been 
  collected. 
  In 
  the 
  cliffs 
  

   near 
  Penarth, 
  probably 
  the 
  most 
  complete 
  section 
  in 
  Britain, 
  nearly 
  

   every 
  known 
  British 
  species 
  has 
  been 
  obtained. 
  This 
  section 
  is 
  

   especially 
  rich 
  in 
  the 
  Mollusca, 
  of 
  which 
  fifteen 
  species 
  occur, 
  and 
  

   ten 
  species 
  of 
  fish 
  ; 
  at 
  Barrow 
  on 
  Soar 
  the 
  complete 
  series 
  was 
  cut 
  

   through 
  ; 
  and 
  the 
  railway-cutting 
  at 
  Elton, 
  near 
  Nottingham, 
  ex- 
  

   hibited 
  the 
  series 
  in 
  conjunction 
  with 
  the 
  Gypsiferous 
  Marls 
  below. 
  

   As 
  far 
  north 
  as 
  Gainsborough 
  they 
  have 
  been 
  continuously 
  traced 
  

   wherever 
  the 
  two 
  series 
  have 
  been 
  seen 
  in 
  position. 
  The 
  generaliza- 
  

   tions 
  dcducible 
  from 
  the 
  deposition 
  of 
  the 
  British 
  liheetics, 
  and 
  what 
  

   we 
  now 
  know 
  concerning 
  the 
  great 
  series 
  in 
  Europe, 
  are 
  numerous 
  

   and 
  important. 
  It 
  is 
  doubtful 
  if 
  any 
  other 
  series 
  affords 
  more 
  scope 
  

   for 
  speculation 
  as 
  to 
  its 
  deposition 
  and 
  accumulation, 
  especially 
  

   •when 
  we 
  know 
  that 
  we 
  have 
  not 
  in 
  the 
  British 
  Islands, 
  in 
  one 
  section 
  

   (or 
  all 
  united), 
  a 
  complete 
  or 
  even 
  representative 
  series 
  of 
  these 
  

  

  * 
  Assuming 
  that 
  there 
  are 
  19 
  species 
  of 
  Ccratodus. 
  

  

  