﻿394 
  MR. 
  H. 
  WOODS 
  ON 
  THE 
  MOLLUSCA 
  [Allg. 
  1 
  897, 
  

  

  Remarks. 
  — 
  I 
  have 
  seen 
  only 
  one 
  example 
  of 
  this 
  from 
  the 
  Chalk 
  

   Rock, 
  which 
  is 
  in 
  the 
  Montagu 
  Smith 
  Collection 
  ; 
  it 
  shows 
  the 
  

   concentric 
  ribs, 
  although 
  the 
  shell 
  is 
  not 
  preserved. 
  This 
  specimen 
  

   agrees 
  perfectly 
  with 
  Sowerby's 
  figure 
  of 
  Leda 
  puldira, 
  but 
  I 
  have 
  

   not 
  succeeded 
  in 
  tracing 
  the 
  type 
  of 
  that 
  species 
  ; 
  it 
  is 
  stated 
  to 
  

   have 
  come 
  from 
  the 
  ' 
  Chalk 
  of 
  Kent.' 
  The 
  English 
  specimens, 
  

   and 
  also 
  the 
  figures 
  given 
  by 
  Goldfuss 
  and 
  Reuss, 
  differ 
  from 
  the 
  

   type 
  in 
  having 
  the 
  posterior 
  part 
  of 
  the 
  shell 
  much 
  shorter 
  ; 
  this, 
  

   however, 
  is 
  probably 
  due 
  to 
  the 
  preservation 
  of 
  the 
  shell 
  in 
  Nilsson's 
  

   original 
  specimen. 
  

  

  Affinities. 
  — 
  Stoliczka 
  x 
  states 
  that 
  this 
  species 
  is 
  closely 
  allied 
  to 
  

   his 
  Necvra 
  detecta 
  (from 
  the 
  Ootatoor 
  Group), 
  ' 
  but 
  it 
  has 
  the 
  poste- 
  

   rior 
  end 
  still 
  narrower 
  and 
  longer, 
  and 
  the 
  beaks 
  incurved 
  in 
  a 
  

   direction 
  perpendicular 
  to 
  the 
  longitudinal 
  axis 
  of 
  the 
  shell.' 
  

  

  Distribution. 
  — 
  Chalk 
  of 
  Kent 
  (horizon 
  unknown). 
  Chalk 
  Rock 
  of 
  

   Cuckhamsley. 
  Westphalia 
  : 
  zone 
  of 
  Ammonites 
  ccesfeldensis 
  (Upper 
  

   Senonian) 
  of 
  Coesfeld. 
  Saxony 
  : 
  Planer-Kalk 
  of 
  Strehlen. 
  Bohemia 
  : 
  

   in 
  the 
  Weissenberg, 
  Malnitz, 
  and 
  Teplitz 
  Beds 
  {fide 
  Fritsch). 
  Ba- 
  

   varia 
  : 
  Grossberg 
  Beds 
  of 
  Marterberg 
  near 
  Passau. 
  Galicia 
  : 
  

   Nagorzany, 
  near 
  Lemberg 
  (fide 
  Favre). 
  

  

  IV. 
  Distribution 
  and 
  Relations 
  of 
  the 
  Fauna. 
  

  

  I 
  have 
  already 
  pointed 
  out 
  that 
  the 
  fauna 
  of 
  the 
  JReussianum- 
  

   zone 
  has 
  a 
  wide 
  range 
  in 
  Europe 
  ; 
  it 
  can 
  be 
  recognized, 
  although 
  

   showing 
  differences 
  in 
  passing 
  from 
  one 
  region 
  to 
  another, 
  in 
  

   Northern 
  France, 
  North-western 
  Germany 
  (Westphalia, 
  Brunswick), 
  

   Saxony, 
  Upper 
  Silesia, 
  Bohemia, 
  and 
  Bavaria. 
  But, 
  though 
  

   traceable 
  in 
  countries 
  so 
  distant 
  as 
  England 
  and 
  Bohemia, 
  it 
  is, 
  

   I 
  believe, 
  absent 
  from 
  the 
  Belgian 
  area 
  ; 
  this 
  is 
  probably 
  to 
  be 
  

   accounted 
  for 
  by 
  the 
  very 
  different 
  conditions 
  under 
  which 
  the 
  

   Cretaceous 
  Series 
  was 
  deposited 
  in 
  Belgium. 
  I 
  hope, 
  however, 
  to 
  

   recur 
  to 
  this 
  point 
  after 
  I 
  have 
  had 
  further 
  opportunities 
  of 
  

   studying 
  the 
  rocks 
  of 
  that 
  country. 
  

  

  The 
  area 
  over 
  which 
  the 
  Meussianum-zone 
  can 
  be 
  traced 
  

   undoubtedly 
  formed 
  part 
  of 
  one 
  life-province 
  in 
  the 
  Cretaceous 
  seas 
  ; 
  

   this 
  province 
  seems 
  to 
  have 
  remained 
  fairly 
  constant 
  throughout 
  the 
  

   Chalk 
  period; 
  it 
  included 
  what 
  Munier-Chalmas 
  2 
  has 
  termed 
  the 
  

   second 
  or 
  temperate 
  zone, 
  which 
  he 
  considers 
  to 
  have 
  been 
  

   especially 
  characterized, 
  in 
  Senonian 
  and 
  Upper 
  Turonian 
  times, 
  by 
  

   the 
  great 
  development 
  of 
  the 
  echinoids 
  Micraster 
  and 
  Echinocorys. 
  

  

  Just 
  as 
  is 
  the 
  case 
  in 
  so 
  many 
  formations, 
  the 
  cephalopoda 
  of 
  the 
  

   Beussianum-zone 
  have 
  a 
  much 
  wider 
  geographical 
  range 
  than 
  the 
  

   gasteropoda 
  and 
  lamellibranchia 
  ; 
  this 
  is 
  no 
  doubt 
  accounted 
  for 
  

   by 
  their 
  more 
  active 
  mode 
  of 
  life. 
  Of 
  the 
  10 
  species 
  of 
  cephalopods 
  

   present 
  in 
  the 
  JReussianum-zone 
  in 
  this 
  country, 
  7 
  occur 
  in 
  Saxony 
  

   and 
  6 
  in 
  Bohemia 
  ; 
  but 
  of 
  the 
  16 
  gasteropods 
  only 
  2 
  (or 
  perhaps 
  3) 
  

   are 
  found 
  in 
  Saxony 
  and 
  2 
  in 
  Bohemia; 
  of 
  the 
  29 
  species 
  of 
  

   lamellibranchs 
  about 
  half 
  have 
  been 
  recognized 
  in 
  Saxony 
  and 
  11 
  

  

  1 
  ' 
  Cret. 
  Fauna 
  S. 
  India,' 
  Pal. 
  Indica, 
  vol. 
  iii. 
  (1870) 
  p. 
  46, 
  pi. 
  iii. 
  f. 
  7 
  

   & 
  pi. 
  xvi. 
  f. 
  15. 
  2 
  Cotnptes 
  Rendus, 
  vol. 
  cxiv. 
  (1892) 
  p. 
  851. 
  

  

  