﻿804 
  PROCEEDINGS 
  OF 
  THE 
  NATIONAL 
  MUSEUM. 
  vol 
  xx. 
  

  

  defining 
  the 
  base 
  of 
  the 
  rostrum. 
  The 
  surface 
  is 
  nearly 
  smooth 
  and 
  

   somewhat 
  glossy, 
  covered 
  with 
  flue 
  lines 
  of 
  growth 
  which 
  become 
  more 
  

   prominent 
  and 
  irreguhir 
  on 
  the 
  rostrum, 
  which 
  has 
  no 
  distinct 
  diagonal 
  

   line. 
  The 
  liinge-mai-gin 
  is 
  somewhat 
  thickened; 
  tlie 
  right 
  valve 
  has 
  a 
  

   rather 
  short, 
  prominent, 
  obtuse, 
  triangular 
  lateral 
  tooth 
  only 
  slightly 
  

   separated 
  from 
  the 
  cartilage-plate 
  by 
  a 
  concave 
  margin; 
  the 
  cartilage- 
  

   plate 
  is 
  small, 
  very 
  oblique, 
  with 
  the 
  inner 
  edge 
  curved 
  and 
  not 
  at 
  all 
  

   angulated. 
  Muscular 
  scars 
  and 
  pallial 
  line 
  indistinct; 
  no 
  buttress. 
  

  

  Length, 
  13 
  mm.; 
  height, 
  9 
  mm.; 
  breadth, 
  G 
  mm.; 
  from 
  beak 
  to 
  end 
  

   of 
  rostrum, 
  8 
  min.; 
  from 
  beak 
  to 
  anterior 
  end, 
  7 
  mm. 
  

  

  Found 
  at 
  about 
  thirty 
  stations 
  between 
  IST. 
  lat. 
  40° 
  2' 
  49", 
  W. 
  long. 
  

   68° 
  49', 
  and 
  N. 
  lat. 
  37° 
  23', 
  W. 
  long. 
  73° 
  53', 
  in 
  302 
  to 
  984 
  ftithoms. 
  

  

  This 
  species 
  resembles 
  C. 
  ohesa 
  (Lov^n) 
  in 
  form; 
  it 
  is, 
  however, 
  a 
  

   larger 
  species 
  with 
  a 
  firmer 
  and 
  more 
  swollen 
  shell; 
  the 
  ventral 
  margin 
  

   is 
  more 
  prominent, 
  so 
  that 
  it 
  has 
  a 
  relatively 
  higher 
  form 
  and 
  is 
  broader 
  

   at 
  the 
  base 
  of 
  the 
  rostrum. 
  The 
  hinge 
  shows 
  more 
  decided 
  differences, 
  

   for 
  in 
  0. 
  ohesa 
  the. 
  lateral 
  tooth 
  is 
  smaller, 
  shorter, 
  and 
  closely 
  approxi- 
  

   mated 
  to 
  the 
  cartilage-plate 
  which 
  is 
  distinctly 
  angulated, 
  the 
  inner 
  

   end 
  being 
  acute 
  and 
  separated 
  from 
  the 
  tooth 
  by 
  a 
  small 
  angular 
  

   notch. 
  

  

  CUSPIDARIA 
  OBESA 
  (Loven) 
  Dall. 
  

   (PlateLXXV, 
  fig. 
  7.) 
  

  

  Newra 
  ohesa 
  LoV]fiN, 
  Ind. 
  Moll. 
  Scand. 
  Occid., 
  p. 
  48, 
  1846.— 
  Veruill, 
  Trans. 
  

  

  Conn. 
  Acad., 
  V, 
  p. 
  563, 
  pi. 
  XLn', 
  fig. 
  10c, 
  1882; 
  VI, 
  p. 
  277, 
  1884 
  (in 
  part) 
  ; 
  Expl. 
  

  

  Albatross, 
  Report 
  U. 
  S. 
  Com. 
  Fish 
  and 
  Fisheries 
  for 
  1883, 
  p. 
  574, 
  1885 
  (in 
  

  

  part). 
  — 
  Smith, 
  E. 
  A., 
  Report 
  Voy. 
  Challenger, 
  Zool. 
  Lamellibrauchiata, 
  XIII, 
  

  

  p. 
  43, 
  1885. 
  

   Cuspidaria 
  ohesa 
  Dall, 
  Bull. 
  Mus. 
  Comp. 
  Zoiil., 
  XII, 
  p. 
  295 
  (not 
  pi. 
  in, 
  fig. 
  1), 
  

  

  1886; 
  Bnll. 
  U. 
  S. 
  Nat. 
  Mus., 
  No. 
  37, 
  p. 
  66 
  (not 
  pi. 
  in, 
  fig. 
  1), 
  1889. 
  

   Not 
  Newra 
  liellucida 
  Stimpson. 
  

  

  This 
  species 
  has 
  been 
  found 
  at 
  about 
  twenty- 
  four 
  stations 
  between 
  N. 
  

   lat. 
  430 
  23', 
  W. 
  long. 
  68° 
  30', 
  and 
  N. 
  lat. 
  35oi2'10", 
  W. 
  long. 
  74o57'15", 
  

   in 
  90 
  to 
  811 
  fathoms, 
  1873-1887. 
  

  

  It 
  is 
  recorded 
  by 
  Mr. 
  Dall 
  from 
  off 
  Barbados 
  in 
  100 
  fathoms 
  and 
  off 
  

   the 
  coast 
  of 
  California 
  in 
  16 
  fathoms. 
  

  

  After 
  a 
  careful 
  study 
  and 
  comparison 
  of 
  the 
  numerous 
  species 
  

   belonging 
  to 
  the 
  family 
  Cuspidaridie 
  we 
  have 
  been 
  able 
  to 
  satisfac- 
  

   torily 
  prove 
  that 
  the 
  form 
  described 
  by 
  Stimpson 
  as 
  Newra 
  pelhicida 
  is 
  

   quite 
  distinct 
  from 
  that 
  described 
  by 
  Loven 
  as 
  X. 
  ohesa, 
  with 
  which 
  it 
  

   has 
  been 
  so 
  long 
  confounded. 
  

  

  