﻿art. 
  25 
  GENERA 
  SIPHOGENERINA 
  AND 
  PAVONINA 
  CUSHMAN 
  15 
  

  

  the 
  test, 
  surface 
  hispid; 
  aperture 
  large, 
  terminal, 
  with 
  a 
  broad 
  

   everted 
  lip, 
  the 
  border 
  of 
  which 
  often 
  has 
  a 
  series 
  of 
  backwardly 
  

   pointing, 
  long, 
  acicular 
  spines. 
  

  

  Length 
  up 
  to 
  1 
  mm. 
  

  

  Distribution. 
  — 
  Except 
  for 
  one 
  record 
  by 
  Brady 
  from 
  the 
  South 
  

   Atlantic, 
  all 
  other 
  records 
  are 
  from 
  the 
  Indo-Pacific. 
  Brady 
  records 
  

   it 
  from 
  several 
  South 
  Pacific 
  stations 
  in 
  12 
  to 
  2,075 
  fathoms. 
  Millett 
  

   notes 
  it 
  as 
  common 
  in 
  his 
  Malay 
  Archipelago 
  material, 
  and 
  Side- 
  

   bottom 
  from 
  off 
  the 
  east 
  coast 
  of 
  Australia. 
  Heron- 
  Allen 
  and 
  Earland 
  

   record 
  it 
  from 
  the 
  Kerimba 
  Archipelago 
  off 
  southeastern 
  Africa 
  and 
  

   from 
  the 
  Antarctic 
  expedition 
  collections. 
  Egger 
  records 
  it 
  from 
  

   off 
  western 
  South 
  Africa 
  and 
  off 
  western 
  Australia. 
  I 
  have 
  had 
  

   abundant 
  material 
  from 
  50 
  fathoms 
  at 
  Samoa. 
  Its 
  Indo-Pacific 
  

   distribution, 
  even 
  though 
  wide, 
  does 
  not 
  include 
  the 
  Philippines 
  nor 
  

   the 
  islands 
  in 
  the 
  Pacific 
  north 
  of 
  the 
  equator. 
  

  

  It 
  is 
  very 
  distinct 
  from 
  other 
  species 
  of 
  the 
  genus 
  in 
  the 
  develop- 
  

   ment 
  of 
  spines 
  from 
  the 
  edge 
  of 
  the 
  lip. 
  

  

  SIPHOGENERINA 
  MEXICANA, 
  new 
  species 
  

  

  Plate 
  5, 
  figs. 
  4a, 
  b 
  

  

  Description. 
  — 
  Test 
  small, 
  elongate, 
  slender, 
  the 
  early 
  portion 
  

   triserial, 
  tapering 
  from 
  a 
  subacute 
  initial 
  end, 
  the 
  later 
  portion 
  

   cylindrical, 
  composed 
  of 
  several 
  chambers 
  — 
  up 
  to 
  eight 
  — 
  in 
  a 
  straight 
  

   line; 
  chambers 
  distinct, 
  those 
  of 
  the 
  later 
  portion 
  inflated; 
  sutures 
  

   distinct, 
  depressed, 
  especially 
  toward 
  the 
  apertural 
  end; 
  wall 
  with 
  

   numerous, 
  rather 
  course 
  punctae, 
  which 
  are 
  almost 
  entirely 
  confined 
  

   to 
  the 
  basal 
  half 
  of 
  each 
  chamber, 
  wall 
  toward 
  the 
  early 
  portion 
  of 
  the 
  

   test 
  with 
  short, 
  longitudinal 
  costae, 
  the 
  later 
  portion 
  of 
  the 
  test 
  

   smooth, 
  thin, 
  translucent; 
  the 
  apertural 
  end 
  truncate 
  with 
  a 
  broad 
  

   elliptical 
  aperture 
  connecting 
  with 
  the 
  previous 
  aperture 
  by 
  an 
  in- 
  

   ternal 
  tubular 
  neck. 
  

  

  Length 
  up 
  to 
  1 
  mm. 
  

  

  Type 
  specimens. 
  — 
  (Cat. 
  No. 
  353174 
  U. 
  S. 
  N. 
  M.) 
  from 
  Rio 
  Buena 
  

   Vista, 
  0.5 
  kms., 
  25°E. 
  from 
  Tumbadero 
  Hacienda 
  House, 
  Vera 
  Cruz, 
  

   Mexico, 
  T. 
  Wayland 
  Vaughan 
  collector. 
  Specimens 
  also 
  are 
  in 
  the 
  

   United 
  States 
  National 
  Museum 
  collections 
  from 
  other 
  localities 
  in 
  the 
  

   Alazan 
  clays 
  in 
  the 
  same 
  general 
  region. 
  The 
  species 
  also 
  occurs 
  in 
  

   the 
  Eocene 
  of 
  the 
  Coastal 
  Plain 
  of 
  the 
  United 
  States. 
  

  

  This 
  species 
  is 
  undoubtedly 
  the 
  ancestor 
  of 
  S. 
  advena 
  Cushman, 
  

   now 
  living 
  in 
  the 
  Gulf 
  of 
  Mexico, 
  the 
  Caribbean 
  Sea, 
  and 
  adjacent 
  

   regions 
  of 
  the 
  western 
  Atlantic. 
  The 
  living 
  species 
  has 
  taken 
  on 
  a 
  

   compressed 
  character 
  of 
  the 
  test; 
  the 
  ornamentation 
  of 
  the 
  basal 
  

   portion 
  is 
  somewhat 
  different, 
  having 
  assumed 
  a 
  spinose 
  condition, 
  

   but 
  the 
  general 
  characters 
  of 
  the 
  two 
  are 
  very 
  much 
  alike. 
  Both 
  

   have 
  the 
  basal 
  portion 
  of 
  the 
  uniserial 
  chambers 
  punctate 
  and 
  the 
  

   distal 
  portion 
  clear, 
  although 
  the 
  relative 
  amount 
  of 
  each 
  is 
  different 
  

   in 
  the 
  two 
  species. 
  

  

  