﻿60 
  PROCEEDINGS 
  OF 
  THE 
  GEOLOGICAL 
  SOCIETY. 
  [NOV. 
  18, 
  

  

  This 
  species 
  is 
  allied 
  to 
  Turbo 
  variabilis 
  and 
  T. 
  petholatus, 
  both 
  

   recent 
  species 
  inhabiting 
  the 
  shores 
  of 
  the 
  Philippine 
  Islands. 
  It 
  

   differs 
  from 
  them 
  in 
  being 
  very 
  much 
  smaller 
  (none 
  of 
  the 
  Javan 
  

   specimens 
  being 
  more 
  than 
  one-half 
  the 
  size 
  of 
  even 
  small 
  examples 
  

   of 
  those 
  species), 
  in 
  the 
  obliquity 
  of 
  its 
  growth, 
  and 
  in 
  its 
  flattened 
  

   base. 
  The 
  lines 
  of 
  growth 
  are 
  discernible, 
  but 
  are 
  not 
  so 
  regular 
  as 
  

   in 
  the 
  allied 
  species 
  just 
  mentioned. 
  

  

  Dimensions. 
  — 
  Figured 
  specimen 
  : 
  length 
  |-J 
  inch, 
  breadth 
  -J-| 
  inch; 
  

   length 
  of 
  aperture 
  -f^ 
  inch, 
  breadth 
  -f^ 
  inch. 
  

  

  Matrix. 
  — 
  White 
  limestone. 
  

  

  17. 
  Bulla, 
  sp. 
  

  

  Several 
  casts 
  of 
  a 
  species 
  allied 
  to 
  the 
  recent 
  Bulla 
  austrdlis 
  are 
  

   contained 
  in 
  M. 
  de 
  Groot's 
  collection 
  ; 
  it 
  is 
  probably 
  distinct, 
  but 
  I 
  

   have 
  not 
  given 
  it 
  a 
  specific 
  name 
  in 
  the 
  hope 
  that 
  more 
  perfect 
  

   specimens 
  may 
  be 
  obtained 
  with 
  the 
  shell 
  still 
  preserved, 
  so 
  as 
  to 
  

   determine 
  whether 
  it 
  had 
  any 
  ornament. 
  The 
  rock 
  composing 
  these 
  

   casts 
  is 
  a 
  greenish-grey 
  marly 
  sandstone, 
  apparently 
  very 
  rich 
  in 
  

   Shells 
  and 
  Corals, 
  as 
  most 
  of 
  the 
  specimens 
  contain 
  fragments 
  of 
  one 
  

   or 
  the 
  other. 
  

  

  18. 
  Cardittm 
  sttbalternatttm, 
  spec. 
  nov. 
  PI. 
  VII. 
  figs. 
  7 
  a, 
  7 
  b. 
  

  

  Casts 
  broadly 
  and 
  obliquely 
  ovate, 
  cordiform 
  in 
  section, 
  com- 
  

   pressed 
  posteriorly, 
  inflated 
  anteriorly, 
  somewhat 
  attenuated 
  towards 
  

   the 
  umbones, 
  and 
  very 
  inequilateral 
  ; 
  anterior 
  side 
  rounded 
  ; 
  poste- 
  

   rior 
  side 
  produced, 
  subangularly 
  rounded, 
  and 
  closed. 
  Surface 
  

   ornamented 
  with 
  from 
  27 
  to 
  29 
  radiating 
  curved 
  ribs, 
  which 
  become 
  

   slightly 
  expanded 
  close 
  to 
  the 
  margin 
  ; 
  between 
  these 
  ribs, 
  especially 
  

   in 
  the 
  anterior 
  region, 
  are 
  smaller, 
  less 
  elevated 
  ridges, 
  which 
  die 
  

   away 
  towards 
  the 
  umbones, 
  and 
  probably 
  correspond 
  to 
  minute 
  alter- 
  

   nate 
  ribs 
  on 
  the 
  shell. 
  

  

  The 
  ribs 
  are 
  not 
  very 
  evident 
  in 
  the 
  extreme 
  posterior 
  region, 
  but 
  

   become 
  inconspicuous 
  behind 
  a 
  broad 
  and 
  rather 
  shallow 
  channel 
  

   or 
  groove, 
  which 
  runs 
  between 
  the 
  two 
  hindermost, 
  well-marked 
  

   costae, 
  and 
  gives 
  that 
  portion 
  of 
  the 
  cast 
  a 
  compressed 
  character 
  ; 
  

   they 
  also 
  become 
  indistinct 
  anteriorly, 
  but 
  there 
  the 
  casts 
  are 
  inflated 
  

   instead 
  of 
  being 
  compressed. 
  

  

  This 
  species 
  appears 
  to 
  be 
  most 
  nearly 
  related 
  to 
  Cardium 
  alter- 
  

   nation, 
  Sow., 
  from 
  the 
  Philippine 
  Islands 
  ; 
  but 
  they 
  differ 
  in 
  the 
  

   former 
  being 
  somewhat 
  more 
  produced 
  and 
  much 
  more 
  compressed 
  

   posteriorly, 
  and 
  not 
  more 
  than 
  one-third 
  the 
  size 
  of 
  the 
  latter. 
  

   There 
  is 
  also 
  no 
  evidence 
  of 
  this 
  being 
  a 
  gaping 
  species 
  (the 
  pos- 
  

   terior 
  compression 
  leading 
  to 
  an 
  opposite 
  conclusion), 
  whilst 
  C. 
  alter- 
  

   natum 
  is 
  slightly 
  so. 
  

  

  Dimensions. 
  — 
  Figured 
  specimen 
  : 
  length 
  1£ 
  inch, 
  breadth 
  1 
  inch, 
  

   thickness 
  | 
  inch. 
  

  

  Matrix. 
  — 
  Some 
  of 
  the 
  casts 
  are 
  composed 
  of 
  a 
  reddish 
  marly 
  sand- 
  

   stone, 
  and 
  some 
  of 
  a 
  greenish 
  sandstone. 
  

  

  