﻿T. 
  DAVIDSON 
  AND 
  W. 
  KING 
  ON 
  THE 
  TEIMERELLID^. 
  

  

  165 
  

  

  Fig. 
  3. 
  — 
  Lingulops 
  Whit- 
  

   fieldi, 
  interior 
  magnified. 
  

  

  cast 
  extends 
  as 
  a 
  narrow 
  groove 
  towards 
  the 
  base 
  of 
  the 
  shell. 
  

   The 
  character 
  of 
  the 
  area 
  and 
  foramen 
  differ 
  from 
  the 
  typical 
  

   forms 
  of 
  Lingulella 
  ; 
  though 
  in 
  that 
  genus 
  the 
  form 
  and 
  character 
  

   of 
  the 
  muscular 
  impression 
  has 
  not 
  been 
  determined, 
  as 
  far 
  as 
  I 
  

   am 
  aware. 
  For 
  this 
  shell 
  I 
  propose 
  the 
  name 
  Lingulops 
  " 
  *. 
  

  

  In 
  plate 
  13, 
  fig. 
  2, 
  of 
  the 
  " 
  Generic 
  illustrations 
  " 
  attached 
  to 
  the 
  

   "Notes" 
  the 
  author 
  has 
  given 
  a 
  view 
  "showing 
  the 
  arrangement 
  

   of 
  some 
  of 
  the 
  muscular 
  and 
  parietal 
  scars, 
  and 
  also 
  the 
  ramifica- 
  

   tions 
  of 
  the 
  vascular 
  lines, 
  which, 
  although 
  originating 
  at 
  nearly 
  

   the 
  same 
  points 
  as 
  in 
  recent 
  Lingulidce, 
  do 
  not 
  extend 
  so 
  far 
  back 
  

   towards 
  the 
  beak." 
  

  

  Professor 
  Hall 
  has 
  liberally 
  supplied 
  us 
  with 
  gutta-percha 
  squeezes 
  

   of 
  this 
  interesting 
  form 
  ; 
  and 
  as 
  his 
  description 
  and 
  figure 
  do 
  not 
  

   afford 
  sufficient 
  information 
  respecting 
  its 
  characters, 
  we 
  have 
  been 
  

   induced 
  to 
  publish 
  the 
  following 
  observations. 
  

  

  The 
  fossil, 
  which 
  is 
  less 
  than 
  two 
  lines 
  in 
  length 
  by 
  one 
  in 
  width, 
  

   is 
  an 
  impression 
  or 
  cast, 
  of 
  the 
  interior 
  and 
  outline 
  of 
  a 
  single 
  valve 
  : 
  

   it 
  shows, 
  however, 
  some 
  characters 
  in 
  a 
  

   remarkably 
  fine 
  state 
  when 
  examined 
  by 
  

   a 
  good 
  pocket-magnifier. 
  Hall's 
  figure, 
  

   taken 
  from 
  the 
  natural 
  impression 
  or 
  the 
  

   fossil 
  itself, 
  exhibits 
  these 
  characters 
  

   with 
  a 
  faulty 
  appearance 
  ; 
  our 
  gutta- 
  

   percha 
  squezees 
  show 
  them 
  in 
  relief, 
  and 
  

   depressed, 
  exactly 
  as 
  they 
  would 
  present 
  

   themselves 
  in 
  the 
  inner 
  side 
  of 
  the 
  valve. 
  

   Even 
  our 
  figure 
  in 
  PL 
  XIX. 
  is 
  not 
  so 
  

   satisfactory 
  as 
  could 
  be 
  desired, 
  as 
  cer- 
  

   tain 
  points 
  have 
  only 
  occurred 
  to 
  us 
  

   since 
  the 
  plate 
  was 
  struck 
  off; 
  for 
  which 
  

   reason 
  we 
  have 
  given 
  an 
  additional 
  figure 
  

   in 
  the 
  annexed 
  woodcut 
  (Fig. 
  3). 
  

  

  The 
  most 
  striking 
  features 
  are 
  : 
  — 
  first, 
  

   the 
  posterior 
  semicircular 
  broad 
  zone, 
  

   with 
  an 
  inner 
  sinused 
  border 
  ; 
  second, 
  the 
  arched 
  fillet 
  situated 
  

   below 
  the 
  hinge, 
  and 
  on 
  the 
  zone 
  ; 
  third, 
  the 
  central 
  space 
  marked 
  

   with 
  scars 
  ; 
  and, 
  fourth, 
  the 
  linear 
  impressions 
  occurring 
  in 
  the 
  

   anterior 
  half 
  of 
  the 
  fossil. 
  The 
  fourth 
  feature, 
  no 
  doubt, 
  represents 
  

   the 
  median 
  plate, 
  and 
  the 
  pair 
  of 
  primary 
  vessels 
  belonging 
  to 
  the 
  

   brachioccele 
  ; 
  the 
  third 
  obviously 
  forms 
  the 
  apophysary 
  system 
  ; 
  the 
  

   second 
  is 
  evidently 
  the 
  equivalent 
  of 
  the 
  crescent 
  characterizing 
  

   the 
  Trimerellids 
  ; 
  but 
  the 
  first 
  we 
  cannot 
  properly 
  identify 
  with 
  any 
  

   part 
  belonging 
  to 
  the 
  Palliobranchs. 
  

  

  Hall 
  is 
  evidently 
  disposed 
  to 
  believe 
  that 
  the 
  fossil 
  represents 
  the 
  

   pedicle-valve 
  (" 
  ventral 
  ") 
  : 
  we, 
  however, 
  entertain 
  a 
  strong 
  idea 
  

   that 
  it 
  belongs 
  to 
  the 
  opposite 
  or 
  brachial 
  valve, 
  notwithstanding 
  

   the 
  statement 
  that 
  it 
  " 
  presents 
  a 
  small 
  area 
  with 
  a 
  narrow 
  pedicel- 
  

  

  * 
  Preliminary 
  Notice 
  ; 
  twenty-third 
  Report 
  on 
  the 
  State 
  Cabinet 
  of 
  Natural 
  

   History 
  for 
  the 
  Palaeontology 
  of 
  New 
  York, 
  March 
  1871, 
  p. 
  2, 
  and 
  reprint 
  of 
  

   the 
  same, 
  March 
  1872, 
  pi. 
  13. 
  fig. 
  2. 
  

  

  