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  PROCEEDINGS 
  OF 
  THE 
  GEOLOGICAL 
  SOCIETY. 
  

  

  and 
  Endothy 
  ra 
  range 
  from 
  the 
  Carboniferous 
  rocks 
  to 
  the 
  present 
  

   day, 
  and, 
  like 
  Gyropella, 
  form 
  entire 
  beds 
  of 
  limestone. 
  The 
  remark- 
  

   able 
  Carboniferous 
  geuus 
  Saeeammina 
  also 
  forms 
  entire 
  beds 
  of 
  lime- 
  

   stone 
  in 
  the 
  Carboniferous 
  rocks 
  of 
  the 
  South 
  of 
  Scotland 
  and 
  the 
  

   North 
  of 
  England, 
  yet 
  from 
  that 
  time, 
  through 
  all 
  the 
  newer 
  de- 
  

   posits, 
  down 
  to 
  the 
  Postpliocene 
  and 
  recent 
  periods 
  it 
  has 
  never 
  

   occurred*. 
  The 
  colossal 
  and 
  complicated 
  genus 
  Parkeria 
  from 
  the 
  

   Cretaceous 
  rocks 
  (Upper 
  Greensand) 
  of 
  Britain, 
  and 
  the 
  fusiform 
  

   Loftusia 
  of 
  Eocene 
  age 
  from 
  Persia, 
  the 
  Miliolm 
  which 
  constitute 
  

   the 
  Eocene 
  Miliolite 
  Limestone 
  of 
  the 
  Paris 
  basin, 
  and 
  which 
  com- 
  

   menced 
  in 
  the 
  Lias, 
  are 
  examples 
  of 
  the 
  Imperforata 
  that 
  have 
  played 
  

   an 
  important 
  part 
  in 
  the 
  seas 
  of 
  the 
  globe, 
  and 
  in 
  the 
  construction 
  

   of 
  the 
  rocks 
  in 
  which 
  they 
  occur. 
  The 
  second 
  suborder, 
  the 
  Per- 
  

   forata, 
  or 
  those 
  having 
  hyaline 
  or 
  vitreous 
  calcareous 
  shells, 
  illus- 
  

   trated 
  by 
  the 
  Lagenida, 
  Globigerinida, 
  and 
  Xummulinida, 
  abound 
  

   in 
  the 
  Trias 
  and 
  Lias. 
  

  

  The 
  most 
  important 
  genera, 
  or 
  those 
  possessing 
  most 
  species, 
  are 
  

   Cristellaria 
  represented 
  by 
  12 
  species, 
  Dentalina 
  17, 
  Marginulina9, 
  

   Planularia 
  8, 
  Polymorphina 
  11, 
  Frondicularia 
  7 
  ', 
  Nodosaria 
  1 
  '. 
  7 
  

   of 
  the 
  23 
  genera 
  have 
  only 
  1 
  species 
  ; 
  3 
  have 
  2 
  species. 
  

  

  84 
  species 
  occur 
  in 
  the 
  Lower 
  Lias, 
  48 
  in 
  the 
  Middle, 
  and 
  33 
  in 
  

   the 
  Upper 
  Lias. 
  The 
  succeeding 
  6 
  stages 
  or 
  horizons 
  possess 
  none 
  ; 
  

   only 
  3 
  species 
  occur 
  in 
  the 
  Oxford 
  Clay, 
  1 
  in 
  the 
  Coral 
  Rag, 
  and 
  13 
  

   in 
  the 
  Kimmcridge 
  Clay. 
  This 
  unequal 
  distribution 
  cannot 
  be 
  

   accounted 
  for 
  on 
  zoological 
  grounds 
  only 
  ; 
  did 
  they 
  occur 
  between 
  

   the 
  Upper 
  Lias 
  and 
  the 
  Kcllaways 
  Rock 
  in 
  Britain, 
  we 
  should 
  

   have 
  observed 
  them 
  ; 
  all 
  evidence 
  tends 
  the 
  other 
  way. 
  10 
  genera 
  

   and 
  17 
  species 
  appear 
  to 
  be 
  common 
  to 
  the 
  Trias 
  (Kcuper 
  marls) 
  

   and 
  Lias, 
  chiefly 
  Lower 
  Lias. 
  None 
  occur 
  in 
  the 
  intermediate 
  Ehaetic 
  

   beds, 
  so 
  far 
  as 
  we 
  know. 
  

  

  Ccelenteeata. 
  Hydrozoa. 
  — 
  I 
  am 
  not 
  aware 
  that 
  any 
  species 
  of 
  

   this 
  class 
  occur 
  in 
  the 
  Jurassic 
  rocks 
  of 
  Britain. 
  The 
  subclass 
  

   Discophora, 
  through 
  the 
  order 
  Medusidae, 
  and 
  the 
  subclass 
  Lucer- 
  

   narida, 
  through 
  the 
  Rhizostomidce, 
  are 
  represented 
  in 
  Jurassic 
  rocks 
  

   on 
  the 
  continent 
  ; 
  the 
  Medusidse, 
  through 
  members 
  of 
  the 
  existing 
  

   families 
  JEquoridce 
  and 
  Trachymenidce, 
  have 
  left 
  their 
  impressions 
  in 
  

   the 
  highly 
  levigated 
  lithographic 
  stone 
  of 
  Solenhofen 
  (Kimmeridge) 
  ; 
  

   and 
  the 
  genus 
  He.varldzltcs 
  of 
  the 
  liliizostomidce 
  represents 
  the 
  

   Lucernarida 
  in 
  the 
  corresponding 
  remarkable 
  deposits 
  at 
  Pappenheim 
  

   and 
  Eichstadt. 
  Doubtless 
  this 
  class 
  was 
  abundantly 
  represented 
  in 
  

   the 
  seas 
  of 
  the 
  Lias 
  and 
  those 
  which 
  laid 
  down 
  the 
  higher 
  Jurassic 
  

   rocks 
  in 
  Britain 
  ; 
  but 
  the 
  delicacy 
  of 
  their 
  tissues 
  and 
  their 
  possessing 
  

   no 
  hard 
  skeleton 
  or 
  structure, 
  and 
  there 
  being 
  no 
  deposit, 
  save 
  the 
  

   "white 
  Lias" 
  at 
  the 
  base 
  of 
  that 
  formation, 
  which 
  could 
  have 
  

   preserved 
  such 
  delicate 
  organisms, 
  would 
  stand 
  in 
  the 
  way 
  of 
  their 
  

   being 
  recognized. 
  

  

  Actinozoa. 
  — 
  17 
  genera 
  and 
  80 
  species 
  have 
  been 
  described 
  from 
  

   the 
  Lias 
  ; 
  13 
  genera 
  and 
  72 
  species 
  from 
  the 
  Lower 
  Lias 
  ; 
  6 
  genera 
  

  

  • 
  * 
  We 
  have 
  here 
  a 
  remarkable 
  instance 
  of 
  the 
  continuity 
  of 
  a 
  genus 
  from 
  the 
  

   Carboniferous 
  period, 
  but 
  which 
  has 
  never 
  been 
  recognized 
  in 
  intermediate 
  strata. 
  

  

  