﻿NO. 
  1139. 
  DEEP- 
  WA 
  TER 
  MOLL 
  USCA— 
  VERB 
  ILL 
  AND 
  B 
  USH. 
  787 
  

  

  nearly 
  straight, 
  slopiug- 
  rapidly 
  from 
  tlie 
  beak; 
  the 
  anterior 
  end 
  is 
  dis- 
  

   tinctly 
  produced, 
  evenly 
  rounded; 
  the 
  ventral 
  margin 
  is 
  slightly 
  but 
  

   regularly 
  convex 
  to 
  the 
  lower 
  posterior 
  fold; 
  the 
  posterior 
  end 
  is 
  

   marked 
  by 
  two 
  distinct 
  jjlicatious 
  separated 
  by 
  a 
  rather 
  prominent 
  

   ridge 
  which, 
  at 
  the 
  margin, 
  appears 
  as 
  a 
  rounded 
  projection 
  separating 
  

   two 
  reentrant 
  curves; 
  the 
  postero-dorsal 
  margin 
  is 
  convex, 
  sloping 
  

   rapidly 
  to 
  the 
  upper 
  plication. 
  The 
  ligamental 
  area 
  is 
  relatively 
  large, 
  

   long, 
  elliptical, 
  defined 
  by 
  a 
  distinct 
  groove. 
  Internally 
  the 
  hinge- 
  

   margin 
  is 
  considerably 
  thickened, 
  especially 
  directly 
  under 
  the 
  beak, 
  

   where 
  there 
  is 
  a 
  slight 
  swelling; 
  the 
  posterior 
  ligament 
  occupies 
  a 
  

   very 
  distinct 
  groove, 
  and 
  extends 
  forward 
  under 
  the 
  tip 
  of 
  the 
  beak. 
  

  

  Length, 
  3.5 
  mm.; 
  height, 
  3.75 
  mm. 
  

  

  The 
  shell 
  here 
  referred 
  to 
  this 
  species 
  appears 
  to 
  agree 
  well 
  with 
  the 
  

   figures 
  and 
  descriptions 
  given 
  by 
  G. 
  O. 
  Sars. 
  It 
  pretty 
  closely 
  resem- 
  

   bles 
  some 
  varieties 
  of 
  C. 
  gouhlii. 
  The 
  x>rincipal 
  differences 
  exter- 
  

   nally 
  are 
  in 
  the 
  somewhat 
  more 
  produced 
  anterior 
  end 
  and 
  the 
  longer 
  

   and 
  straighter 
  antero-dorsal 
  margin; 
  the 
  posterior 
  plications 
  are 
  also 
  

   less 
  strongly 
  developed. 
  

  

  Found 
  in 
  small 
  numbers 
  at 
  about 
  thirty 
  stations 
  north 
  of 
  Cape 
  Cod, 
  

   between 
  N. 
  lat. 
  43° 
  U^', 
  W. 
  long. 
  09° 
  22', 
  and 
  :N'. 
  lat. 
  42° 
  30', 
  W. 
  long. 
  

   70O 
  38', 
  in 
  13 
  to 
  73 
  fathoms, 
  1873-1879. 
  

  

  CRYPTODON 
  CROULINENSIS 
  (Jeffreys) 
  Smith, 
  variety 
  ALTUS, 
  new. 
  

   (Pint.! 
  LXXXVIII, 
  iig.s. 
  1, 
  2.) 
  

  

  Shell 
  higher 
  than 
  long, 
  larger 
  than 
  the 
  common 
  form. 
  Umbos 
  promi- 
  

   nent, 
  elevated 
  and 
  turned 
  forward, 
  so 
  as 
  to 
  leave 
  a 
  rather 
  large, 
  con- 
  

   spicuous, 
  flattened, 
  lunular 
  area, 
  which 
  is 
  bordered 
  externally 
  by 
  a 
  

   slight 
  ridge, 
  followed 
  by 
  a 
  concave 
  depression 
  in 
  the 
  surface, 
  which 
  

   forms 
  a 
  slight 
  indentation 
  in 
  the 
  anterior 
  margin, 
  and 
  resembles 
  the 
  

   posterior 
  plication, 
  but 
  is 
  more 
  shallow. 
  The 
  antero-dorsal 
  margin 
  in 
  

   the 
  lunular 
  region 
  is 
  slightly 
  concave, 
  but 
  slopes 
  very 
  rapidly; 
  the 
  

   anterior 
  end 
  is 
  a 
  little 
  more 
  produced 
  than 
  the 
  posterior, 
  but 
  both 
  are 
  

   decidedly 
  short; 
  the 
  ventral 
  margin 
  is 
  pretty 
  evenly 
  rounded; 
  poste- 
  

   riorly 
  there 
  are 
  two 
  distinct 
  iilications; 
  the 
  lower 
  or 
  larger 
  one 
  is 
  mod- 
  

   erately 
  sunken 
  and 
  extends 
  from 
  the 
  beak 
  to 
  the 
  posterior 
  margin, 
  

   the 
  upper 
  one 
  is 
  much 
  shorter 
  and 
  narrower 
  and 
  defines 
  the 
  narrow, 
  

   lanceolate, 
  ligamental 
  area; 
  each 
  produces 
  a 
  decided 
  indentation 
  in 
  

   the 
  margin, 
  that 
  caused 
  by 
  the 
  lower 
  one 
  being 
  more 
  sharply 
  defined 
  

   and 
  shorter 
  than 
  the 
  other, 
  these 
  are 
  separated 
  by 
  a 
  well-defined, 
  

   curved, 
  radiating 
  ridge 
  which 
  extends 
  a 
  little 
  below 
  the 
  margin; 
  the 
  

   postero-dorsal 
  margin 
  is 
  strongly 
  convex, 
  evenly 
  rounded, 
  with 
  a 
  rapid 
  

   slope; 
  the 
  hinge 
  margin 
  is 
  considerably 
  thickened, 
  especially 
  beneath 
  

   the 
  beak, 
  and 
  in 
  the 
  right 
  valve 
  forms 
  a 
  distinctly 
  raised 
  tubercle. 
  

  

  Length, 
  5 
  mm. 
  ; 
  height, 
  C 
  mm. 
  Eastport, 
  Maine, 
  1870. 
  

  

  Another 
  si)ecimen, 
  from 
  station 
  292, 
  is 
  slightly 
  smaller. 
  Length, 
  

  

  