﻿WRIGHT 
  AND 
  ADAMS 
  MALTESE 
  ECHLNODERMS. 
  483 
  

  

  slightly 
  arched 
  from 
  front 
  to 
  back. 
  The 
  peristome 
  is 
  nearer 
  the 
  

   anterior 
  border 
  ; 
  its 
  form 
  is 
  indistinct 
  from 
  adherent 
  matrix 
  ; 
  it 
  

   appears 
  to 
  be 
  obliqne 
  and 
  angular. 
  The 
  poriferous 
  zones 
  descend 
  

   to 
  the 
  margin 
  without 
  doubling. 
  The 
  vent 
  is 
  large 
  and 
  oblong, 
  one 
  

   extremity 
  approaching 
  the 
  peristome, 
  the 
  other 
  reaching 
  nearly 
  to 
  the 
  

   border, 
  and 
  occupying 
  much 
  of 
  the 
  basal 
  portion 
  of 
  the 
  interam- 
  

   bulacrum. 
  The 
  apical 
  disk 
  is 
  small 
  and 
  excentral, 
  with 
  four 
  

   ovarian 
  pores 
  ; 
  the 
  tubercles 
  are 
  small, 
  equal, 
  and 
  closely 
  set. 
  

  

  Affinities 
  and 
  differences. 
  — 
  It 
  resembles 
  A. 
  apJieles, 
  Ag., 
  from 
  the 
  

   ferruginous 
  Nummulitic 
  bed 
  at 
  Verona 
  ; 
  but 
  it 
  diners 
  from 
  that 
  

   species 
  in 
  having 
  the 
  test 
  a 
  regular 
  ovoid, 
  not 
  tapering 
  behind, 
  and 
  

   in 
  possessing 
  a 
  larger 
  vent. 
  

  

  Stratigraphical 
  position. 
  — 
  Collected 
  from 
  bed 
  No. 
  1, 
  the 
  Upper 
  

   Limestone, 
  at 
  Malta, 
  where 
  it 
  is 
  extremely 
  rare. 
  

  

  19. 
  CoNOCLYPTJS 
  PLAGIOSOMTJS, 
  Agassiz. 
  

  

  Stratigrapliical 
  position. 
  — 
  " 
  I 
  have 
  met 
  with 
  this 
  Urchin 
  pretty 
  

   often 
  in 
  the 
  red 
  and 
  yellow 
  Sand-bed 
  No. 
  2, 
  chiefly 
  in 
  the 
  redder 
  

   portions. 
  The 
  specimen 
  from 
  No. 
  4 
  I 
  am 
  disposed 
  to 
  consider 
  speci- 
  

   fically 
  identical 
  with 
  those 
  from 
  No. 
  2. 
  It 
  is 
  rare, 
  and 
  when 
  met 
  

   with 
  is 
  usually 
  seen 
  in 
  fragments. 
  All 
  I 
  have 
  found 
  have 
  been 
  in 
  the 
  

   nodule-beds 
  of 
  No. 
  4. 
  The 
  difference 
  in 
  shape 
  of 
  the 
  specimens 
  in 
  

   the 
  collection 
  is 
  evidently 
  the 
  result 
  of 
  pressure." 
  (A. 
  L. 
  A.) 
  

  

  Collections 
  and 
  localities.— 
  Bristol 
  Museum; 
  Royal 
  School 
  of 
  Mines 
  ; 
  

   Earl 
  of 
  Ducie's 
  Coll. 
  ; 
  my 
  cabinet. 
  Balistro, 
  Corsica 
  ; 
  Molasse 
  du 
  

   Cap 
  Couronne, 
  pres 
  Martigues 
  (Michelin) 
  ; 
  d' 
  Alicante 
  (Deluc) 
  ; 
  

   Earedjah 
  and 
  Santarieh, 
  west 
  of 
  Egypt 
  (Desor). 
  

  

  20. 
  Hemiaster 
  Cotteaui, 
  Wright. 
  

  

  Stratigraphical 
  position. 
  — 
  " 
  Collected 
  from 
  bed 
  No. 
  4, 
  the 
  Calca- 
  

   reous 
  Sandstone, 
  at 
  Malta. 
  I 
  have 
  not 
  found 
  it 
  in 
  any 
  collection 
  of 
  

   Miocene 
  fossils. 
  What 
  appears 
  to 
  me 
  a 
  specimen 
  of 
  this 
  Urchin 
  from 
  

   No. 
  1 
  bed 
  is, 
  however, 
  a 
  very 
  imperfect 
  example. 
  The 
  specimens 
  from 
  

   beds 
  Nos. 
  4 
  and 
  5 
  certainly 
  belong 
  to 
  this 
  species 
  ; 
  should 
  there 
  be 
  

   any 
  doubt 
  as 
  to 
  that 
  from 
  No. 
  1, 
  we 
  had 
  better 
  discard 
  it 
  and 
  wait 
  for 
  

   more 
  authentic 
  information. 
  H. 
  Cotteaui 
  is 
  a 
  common 
  Urchin 
  in 
  

   No. 
  4, 
  and 
  is 
  nearly 
  always 
  associated 
  with 
  H. 
  Scillce, 
  especially 
  in 
  

   the 
  weather- 
  and 
  surf- 
  worn 
  rocks 
  around 
  the 
  harbour 
  of 
  Yaletta, 
  

   where 
  it 
  may 
  be 
  seen 
  in 
  groups 
  on 
  the 
  shelving 
  parts, 
  with 
  the 
  

   ambulacral 
  surfaces 
  lying 
  uppermost, 
  as 
  if 
  the 
  animals 
  had 
  died 
  

   where 
  they 
  are 
  now 
  found. 
  I 
  may 
  remark 
  that 
  this 
  is 
  generally 
  

   the 
  case 
  with 
  all 
  Echinoderms 
  of 
  No. 
  4, 
  excepting 
  those 
  in 
  the 
  

   nodule-beds, 
  where 
  the 
  fossils 
  are 
  all 
  jumbled 
  together. 
  It 
  is 
  met 
  

   with 
  in 
  the 
  nodule-beds, 
  also 
  in 
  the 
  upper 
  portions 
  of 
  No. 
  5, 
  where 
  

   it 
  is 
  common." 
  (A. 
  L. 
  A.) 
  

  

  21. 
  Hemiaster 
  Scill^e, 
  Wright. 
  

  

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

   the 
  other 
  species 
  of 
  the 
  genus 
  just 
  named. 
  It 
  is 
  also 
  plentiful 
  in 
  the 
  

   transition 
  and 
  upper 
  portions 
  of 
  No. 
  5 
  ; 
  but 
  all 
  the 
  specimens 
  I 
  

  

  