﻿NO. 
  1139. 
  DEEV- 
  WA 
  TEB 
  MOLL 
  USCA— 
  VERRLLL 
  AND 
  B 
  USE. 
  8 
  45 
  

  

  middle, 
  where 
  it 
  is 
  narrowest, 
  it 
  is 
  nearly 
  smooth 
  and 
  rounded, 
  with 
  

   oiily 
  slight 
  indications 
  of 
  one 
  or 
  two 
  transverse 
  teeth 
  on 
  each 
  side; 
  

   next 
  these 
  there 
  are 
  two 
  or 
  three 
  somewhat 
  oblique, 
  sligiitly 
  divergent, 
  

   irregular, 
  longitudinal, 
  slightly 
  striated 
  and 
  creuulated 
  folds, 
  separated 
  

   distally 
  by 
  ratlier 
  deep 
  grooves 
  nearly 
  parallel 
  with 
  the 
  inner 
  margin. 
  

   The 
  inner 
  edge 
  of 
  the 
  ventral 
  margin 
  is 
  thin 
  and 
  plain. 
  

  

  Length, 
  8.5 
  mm.; 
  height, 
  7 
  mm.; 
  thickness, 
  G 
  mm. 
  

  

  One 
  living 
  specimen 
  (Ko. 
  74081) 
  was 
  dredged 
  by 
  the 
  Bache 
  at 
  station 
  

   52, 
  oft' 
  Cashes 
  Ledge, 
  in 
  27 
  fathoms, 
  1S74. 
  

  

  As 
  only 
  a 
  single 
  specimen 
  has 
  been 
  found, 
  it 
  is 
  possible 
  that 
  it 
  is 
  but 
  

   an 
  abnormal 
  variety, 
  although 
  it 
  appears 
  to 
  have 
  been 
  healthy 
  and 
  

   well-grown 
  in 
  every 
  respect. 
  It 
  is 
  related 
  to 
  B 
  pectxnc 
  id 
  aides 
  (Plate 
  

   LXXVII, 
  tig. 
  ()), 
  but 
  differs 
  remarkably 
  in 
  the 
  character 
  of 
  the 
  hinge, 
  

   which 
  has 
  the 
  transverse 
  teeth 
  scarcely 
  discernible, 
  and 
  oblique, 
  irreg- 
  

   ular 
  folds 
  on 
  the 
  distal 
  parts 
  of 
  the 
  margin, 
  and 
  also 
  in 
  the 
  greater 
  

   width 
  of 
  the 
  ligamental 
  area. 
  

  

  Family 
  LIMOPSID.E. 
  

  

  LIMOPSIS 
  SULCATA, 
  new 
  species. 
  

  

  (Platea 
  XCII, 
  tig-. 
  2; 
  XCV, 
  tig-. 
  9; 
  XCVI, 
  iig. 
  1.) 
  

  

  Shell 
  very 
  oblique 
  (young 
  specimens 
  are 
  less 
  oblique 
  and 
  in 
  some 
  

   cases 
  are 
  more 
  nearly 
  circular), 
  broad 
  ovate, 
  the 
  posterior 
  ventral 
  mar- 
  

   gin 
  much 
  produced 
  and 
  obtusely 
  rounded 
  ; 
  auricles 
  only 
  slightly 
  devel- 
  

   oped. 
  The 
  dorsal 
  margin 
  is 
  short 
  and 
  straight, 
  with 
  a 
  narrow, 
  smooth 
  

   area 
  beneath 
  the 
  beaks; 
  the 
  anterior 
  margin 
  is 
  subtruncate, 
  or 
  very 
  

   obtusely 
  rounded; 
  the 
  ventral 
  margin 
  is 
  oblique, 
  broadly 
  rounded, 
  

   forming 
  an 
  obtusely 
  rounded 
  angle 
  with 
  the 
  ])osterior 
  margin, 
  which 
  is 
  

   strongly 
  sloping 
  and 
  only 
  a 
  little 
  convex. 
  The 
  umbos 
  are 
  small 
  and 
  

   somewhat 
  prominent; 
  the 
  beaks 
  small. 
  ])ointed, 
  and 
  curved 
  inward. 
  

   The 
  entire 
  surface 
  is 
  covered 
  with 
  stiongiy 
  marked, 
  concentric 
  grooves 
  

   and 
  prominent 
  rounded, 
  narrow 
  ribs; 
  the 
  latter 
  are 
  crossed 
  by 
  numer- 
  

   ous 
  tine, 
  radiating, 
  incised 
  striations, 
  which 
  divide 
  tliem 
  into 
  beadlike, 
  

   or 
  squarish, 
  x)ortions, 
  which 
  are 
  most 
  obvions 
  on 
  the 
  middle 
  and 
  pos- 
  

   terior 
  parts 
  and 
  become 
  very 
  faint 
  anteriorly. 
  The 
  hinge-margin 
  is 
  

   much 
  thickened 
  and 
  bears 
  a 
  curved 
  series 
  of 
  rather 
  large, 
  flattened 
  

   teeth, 
  of 
  which 
  about 
  eight 
  are 
  situated 
  in 
  front 
  of 
  the 
  beaks 
  and 
  about 
  

   ten 
  behind 
  them; 
  those 
  nearest 
  the 
  center 
  are 
  small; 
  the 
  resilinl 
  pit 
  

   extends 
  upward 
  to 
  the 
  beak 
  in 
  the 
  form 
  of 
  a 
  small 
  triangular 
  dei)ression. 
  

   The 
  inner 
  surface 
  of 
  the 
  shell 
  is 
  marked 
  by 
  tine, 
  radiating 
  stria^; 
  the 
  

   margin 
  is 
  thickened 
  and 
  cut 
  away 
  near 
  the 
  edge; 
  no 
  creuulations 
  have 
  

   been 
  observed 
  in 
  our 
  specimens. 
  

  

  Greatest 
  length, 
  12 
  mm.; 
  greatest 
  height, 
  13 
  mm.; 
  breadth, 
  6 
  mm. 
  

  

  A 
  number 
  of 
  separate 
  valves, 
  at 
  about 
  ten 
  stations, 
  between 
  J^. 
  lat. 
  

   10° 
  8', 
  W. 
  long. 
  08° 
  45', 
  and 
  N. 
  lat. 
  37° 
  7' 
  4", 
  W. 
  long. 
  74° 
  35' 
  40", 
  iu 
  

   64 
  to 
  349 
  fathoms, 
  1880-1884. 
  

  

  