﻿48-4 
  PROCEEDINGS 
  OF 
  THE 
  GEOLOGICAL 
  SOCIETY. 
  

  

  have 
  met 
  with 
  hitherto 
  from 
  the 
  latter 
  bed 
  have 
  been 
  very 
  small. 
  

   It 
  is 
  also 
  common 
  in 
  the 
  nodule-beds 
  of 
  No. 
  4." 
  (A. 
  L. 
  A.) 
  

  

  22. 
  Beissopsis 
  Duciei, 
  Wright. 
  

  

  iStratigrapliical 
  position. 
  — 
  " 
  All 
  the 
  specimens 
  have 
  been 
  collected 
  

   from 
  the 
  Upper 
  Limestone 
  No. 
  1, 
  and 
  its 
  white 
  sandstone-stratum, 
  

   where 
  the 
  Urchin 
  is 
  very 
  uncommon." 
  (A. 
  L. 
  A.) 
  

  

  Collections. 
  — 
  Earl 
  of 
  Ducie's 
  Coll. 
  ; 
  Museum 
  of 
  the 
  Geological 
  

   Society 
  ; 
  my 
  cabinet. 
  

  

  23. 
  Brissopsis 
  Grateloupi, 
  Sismonda. 
  

  

  Stratigraphical 
  position. 
  — 
  " 
  This 
  Urchin 
  is 
  common 
  in 
  bed 
  No. 
  4, 
  

   and 
  its 
  nodule-beds 
  immediately 
  overlying 
  No. 
  5, 
  associated 
  with 
  

   Hemiaster 
  Scillce, 
  Wright, 
  and 
  H. 
  Cotteaui, 
  Wright. 
  It 
  is 
  likewise 
  

   found 
  in 
  the 
  upper 
  portion 
  of 
  No. 
  5." 
  (A. 
  L. 
  A.) 
  

  

  Collections. 
  — 
  Museum 
  of 
  the 
  Geological 
  Society 
  ; 
  my 
  cabinet. 
  

  

  24. 
  Schtzaster 
  Scill.e, 
  Desmoulins. 
  

  

  Stratigrapliical 
  position. 
  — 
  If 
  I 
  am 
  correct 
  as 
  to 
  the 
  determination 
  

   of 
  the 
  specimens 
  I 
  have 
  thus 
  named, 
  there 
  are 
  in 
  Dr. 
  Leith 
  Adams's 
  

   collection 
  representatives 
  from 
  beds 
  Nos. 
  1, 
  2, 
  4, 
  and 
  5. 
  The 
  large 
  

   specimens 
  from 
  No. 
  1 
  abound 
  in 
  the 
  white 
  calcareous 
  sandstone- 
  

   stratum 
  of 
  that 
  bed, 
  and 
  are 
  most 
  usually 
  associated 
  with 
  Oysters, 
  

   Pectens, 
  &c, 
  to 
  be 
  noticed 
  hereafter. 
  

  

  I 
  have 
  furnished 
  a 
  series 
  of 
  No. 
  1 
  specimens 
  to 
  show 
  their 
  grada- 
  

   tion. 
  The 
  apical 
  disk 
  in 
  several 
  is 
  much 
  nearer 
  the 
  centre 
  of 
  the 
  

   test 
  than 
  in 
  others. 
  

  

  " 
  This 
  Urchin 
  appears 
  occasionally 
  in 
  the 
  black 
  and 
  yellow 
  sand 
  at 
  

   its 
  passage 
  into 
  the 
  subjacent 
  clay 
  (No. 
  3) 
  ; 
  the 
  specimens 
  are 
  similar 
  

   to 
  those 
  from 
  No. 
  4, 
  both 
  in 
  size 
  and 
  configuration, 
  excepting 
  one 
  

   description, 
  of 
  which 
  I 
  have 
  sent 
  several 
  specimens 
  ; 
  in 
  these 
  the 
  

   single 
  ambulacrum 
  is 
  not 
  nearly 
  so 
  broad 
  ; 
  and 
  I 
  have 
  not 
  seen 
  any 
  

   from 
  the 
  calcareous 
  sandstone 
  or 
  the 
  overlying 
  bed 
  which 
  equal 
  in 
  

   size 
  those 
  from 
  No. 
  1. 
  There 
  are 
  likewise 
  several 
  from 
  the 
  nodular 
  

   bed 
  of 
  No. 
  4, 
  all 
  small 
  or 
  young 
  specimens. 
  The 
  single 
  individual 
  

   from 
  No. 
  5 
  is 
  the 
  only 
  one 
  I 
  have 
  seen. 
  I 
  procured 
  it 
  from 
  the 
  

   Lower 
  Limestone 
  at 
  the 
  fault 
  or 
  gorge 
  of 
  Air 
  Selina, 
  Gozo. 
  Like 
  

   the 
  others 
  it 
  differs 
  in 
  some 
  particulars 
  from 
  the 
  type-specimens 
  of 
  

   the 
  upper 
  rock, 
  and 
  possibly 
  I 
  may 
  be 
  incorrect 
  in 
  my 
  diagnosis, 
  and 
  

   have 
  been 
  confounding 
  different 
  species 
  with 
  each 
  other." 
  (A. 
  L. 
  A.) 
  

  

  Collections. 
  — 
  In 
  almost 
  all 
  collections 
  of 
  Maltese 
  Echinoderms. 
  

  

  25. 
  Schizaster 
  Parkinsoni, 
  Defrance. 
  

  

  Stratigraphical 
  position. 
  — 
  " 
  Of 
  this 
  I 
  have 
  sent 
  a 
  series. 
  There 
  are 
  

   specimens 
  from 
  No. 
  1, 
  where 
  it 
  is 
  rare. 
  It 
  is 
  the 
  most 
  common 
  

   Urchin 
  in 
  No. 
  4, 
  where 
  it 
  will 
  be 
  seen 
  there 
  is 
  some 
  variety. 
  I 
  have 
  

   found 
  it 
  not 
  easy 
  to 
  distinguish 
  at 
  all 
  times 
  between 
  specimens 
  of 
  

   S. 
  Desori 
  and 
  this 
  species. 
  There 
  are 
  ten 
  broken 
  specimens 
  from 
  

   No. 
  5 
  bed, 
  which 
  I 
  take 
  to 
  be 
  this 
  species 
  ; 
  but 
  in 
  case 
  of 
  error 
  I 
  will 
  

   attempt 
  to 
  procure 
  more 
  perfect 
  individuals 
  from 
  that 
  bed." 
  (A.L. 
  A.) 
  

  

  