﻿1 
  62 
  PROCEEDINGS 
  OF 
  THE 
  GEOLOGICAL 
  SOCIETY. 
  

  

  strata 
  up 
  to 
  the 
  Limestone 
  rock, 
  or 
  " 
  Bock-bed." 
  In 
  Rutlandshire, 
  

   as 
  in 
  Dorsetshire, 
  Stephanoceras 
  commune 
  and 
  S. 
  annulatum 
  are 
  

   occasionally 
  associated 
  with 
  the 
  Marlstone, 
  or 
  Middle-Lias 
  species, 
  

   Amaltheus 
  spinatus 
  ; 
  yet 
  they 
  cannot 
  be 
  said 
  to 
  occur 
  normally 
  

   together. 
  Amaltheus 
  spinatus 
  occupies 
  the 
  summit 
  of 
  the 
  Middle 
  

   Lias, 
  and 
  is 
  immediately 
  succeeded 
  by 
  Stephanoceras 
  commune 
  

   and 
  S. 
  annulatum. 
  This 
  division 
  of 
  the 
  Lias 
  constitutes 
  a 
  striking 
  

   physical 
  feature 
  all 
  through 
  England, 
  especially 
  in 
  the 
  Midland 
  

   counties 
  ; 
  and 
  its 
  fossil 
  contents 
  are 
  equally 
  marked. 
  The 
  Middle 
  

   Lias 
  of 
  Rutlandshire 
  has 
  been 
  described 
  by 
  Professor 
  Judd 
  * 
  ; 
  and 
  

   every 
  species 
  known 
  therein 
  has 
  been 
  carefully 
  noted 
  by 
  him. 
  He 
  

   names 
  5 
  species 
  of 
  Ammonites, 
  4 
  of 
  Belemnites, 
  7 
  genera 
  and 
  

   12 
  species 
  of 
  the 
  group 
  Dimyaria, 
  and 
  11 
  genera 
  and 
  13 
  species 
  of 
  

   Monomyaria, 
  or 
  27 
  genera 
  and 
  41 
  species, 
  besides 
  the 
  characteristic 
  

   species 
  of 
  Brachiopoda, 
  to 
  be 
  obtained 
  from 
  the 
  Marlstone 
  of 
  Rut- 
  

   landshire. 
  The 
  Middle 
  Lias 
  of 
  Gloucestershire, 
  Dorsetshire, 
  Somer- 
  

   setshire, 
  Northamptonshire, 
  and 
  Lincolnshire 
  yields 
  the 
  same 
  forms, 
  

   the 
  fauna 
  being 
  more 
  or 
  less 
  specifically 
  abundant. 
  

  

  The 
  important 
  upper 
  division 
  of 
  the 
  Middle 
  Lias, 
  or 
  the 
  zone 
  of 
  

   Amaltheus 
  spinatus, 
  must 
  be 
  seen, 
  to 
  be 
  understood, 
  in 
  all 
  areas. 
  

   In 
  Yorkshire, 
  as 
  before 
  stated, 
  it 
  is 
  finely 
  developed, 
  physically 
  and 
  

   palaeontologically. 
  Hawsker 
  Cliffs, 
  Staithes, 
  Boulby, 
  and 
  the 
  Cleve- 
  

   land 
  area 
  all 
  yield 
  an 
  abundant 
  Lamellibranchiate 
  fauna. 
  Between 
  

   40 
  and 
  50 
  species 
  of 
  Dimyaria, 
  belonging 
  to 
  25 
  genera, 
  enrich 
  the 
  

   Spinatus-beds. 
  Everywhere 
  on 
  the 
  continent 
  it 
  is 
  the 
  same; 
  in 
  

   Germany, 
  France, 
  and 
  Belgium, 
  all 
  sections 
  yield 
  the 
  same 
  species. 
  

   The 
  succeeding 
  Upper 
  Lias, 
  with 
  Harpoceras 
  setpentinum 
  and 
  

   H. 
  bifrons, 
  everywhere 
  when 
  fully 
  developed 
  yields 
  proportionately 
  

   about 
  the 
  same 
  number 
  of 
  genera 
  and 
  species 
  of 
  Lamellibranchiata, 
  

   and 
  always 
  the 
  same 
  Ammonites. 
  The 
  general 
  condition 
  of 
  the 
  

   Upper 
  Lias 
  and 
  its 
  fauna 
  is 
  delineated 
  by 
  Prof. 
  Judd 
  in 
  the 
  memoir 
  

   on 
  Rutland 
  just 
  quoted 
  (loc. 
  cit. 
  pp. 
  79-89). 
  I 
  cannot 
  pass 
  over 
  

   the 
  important 
  paper 
  " 
  On 
  the 
  Lias 
  of 
  Dorsetshire," 
  by 
  Mr. 
  E. 
  H. 
  

   Day, 
  published 
  in 
  1863 
  t. 
  Mr. 
  Day 
  has 
  done 
  mOre 
  to 
  elucidate 
  the 
  

   physical 
  history 
  and 
  palaeontology 
  of 
  the 
  Middle 
  and 
  Upper 
  Lias 
  of 
  

   Dorsetshire 
  than 
  any 
  other 
  investigator. 
  It 
  was 
  at 
  my 
  suggestion, 
  

   after 
  I 
  had 
  prepared 
  measured 
  sections 
  of 
  the 
  beds 
  on 
  the 
  coast, 
  

   that 
  Mr. 
  Day 
  undertook 
  to 
  describe 
  all 
  above 
  the 
  Lower 
  Lias. 
  Sir 
  

   H. 
  de 
  la 
  Beche, 
  thirty-four 
  years 
  previously 
  (1829), 
  had, 
  in 
  the 
  

   'Geol. 
  Trans.' 
  2 
  ser. 
  vol. 
  ii., 
  described 
  generally 
  the 
  succession 
  

   on 
  lithological 
  grounds. 
  Much 
  was 
  known 
  of 
  the 
  details 
  of 
  the 
  

   Lower 
  Lias 
  through 
  the 
  extensive 
  collections 
  made 
  " 
  along 
  shore 
  " 
  

   for 
  saurians 
  and 
  fish 
  %. 
  I 
  can 
  do 
  no 
  more 
  than 
  refer 
  to 
  Mr. 
  Day's 
  

   paper 
  for 
  his 
  physical 
  facts, 
  and 
  give 
  his 
  results 
  as 
  to 
  the 
  fossil 
  con- 
  

   tents 
  of 
  the 
  zones 
  or 
  particular 
  beds. 
  The 
  Middle 
  Lias 
  of 
  Black 
  Ven, 
  

  

  * 
  Mem. 
  Geol. 
  Surv., 
  " 
  Geol. 
  of 
  Kutland," 
  &c. 
  pp. 
  64-78, 
  J. 
  W. 
  Judd, 
  F.G.S. 
  

   1875. 
  

  

  1 
  Quart. 
  Journ. 
  Geol. 
  vol. 
  xix. 
  p. 
  278. 
  

  

  % 
  The 
  great 
  series 
  of 
  fossil 
  fish 
  in 
  the 
  possession 
  of 
  Lord 
  Enniskillen 
  and 
  the 
  

   late 
  Sir 
  Philip 
  Egerton 
  came 
  from 
  the 
  Lower 
  Lias, 
  which 
  ranges 
  from 
  Pinhay 
  

   Bay 
  to 
  the 
  foot 
  of 
  Black 
  Ven, 
  the 
  Middle 
  Lias 
  yielding 
  few 
  forms. 
  

  

  