﻿36 
  PROCEEDINGS 
  OF 
  THE 
  NATIONAL 
  MUSEUM 
  vol.98 
  

  

  2% 
  in 
  its 
  length; 
  lower 
  jaw 
  a 
  little 
  shorter 
  than 
  upper, 
  sliglitly 
  in- 
  

   cluded; 
  teeth 
  minute 
  in 
  both 
  jaws 
  in 
  a 
  narrow 
  villiform 
  band. 
  

  

  The 
  following 
  counts 
  were 
  made, 
  respectively 
  : 
  Dorsal 
  rays, 
  IV-I, 
  i, 
  

   8; 
  V-I, 
  i, 
  7; 
  and 
  IV-I, 
  i, 
  7. 
  Anal 
  rays 
  I, 
  i, 
  14; 
  I, 
  i, 
  14; 
  and 
  I, 
  i, 
  14. 
  

  

  Pelvics 
  always 
  I, 
  5. 
  Pectoral 
  rays 
  ; 
  i, 
  12-i, 
  12; 
  and 
  i, 
  12. 
  

  

  Branched 
  caudal 
  rays 
  15; 
  15; 
  15. 
  Scales 
  above 
  lateral 
  line 
  to 
  first 
  

   dorsal 
  origin 
  3I/2; 
  3i/^; 
  3I/2? 
  and 
  below 
  lateral 
  line 
  to 
  anal 
  origin 
  2i/^; 
  

   2^2 
  ; 
  ^nd 
  21/2. 
  Scales 
  in 
  the 
  lateral 
  line 
  44; 
  44 
  ; 
  44. 
  Scales 
  in 
  front 
  of 
  

   first 
  dorsal 
  to 
  rear 
  of 
  pigmented 
  area 
  over 
  brain, 
  20 
  ; 
  21 
  ; 
  20. 
  Scales 
  

   between 
  anal 
  origin 
  and 
  anus 
  4 
  ; 
  4 
  ; 
  4. 
  Scales 
  between 
  dorsal 
  bases 
  of 
  

   dorsal 
  fins 
  7 
  ; 
  7 
  ; 
  6. 
  Zigzag 
  scales 
  around 
  least 
  depth 
  of 
  caudal 
  peduncle 
  

  

  12 
  ; 
  12 
  ; 
  and 
  12. 
  Gill 
  rakers 
  on 
  first 
  gill 
  arch 
  4 
  + 
  1 
  + 
  14 
  ; 
  ; 
  and 
  

  

  2 
  + 
  1 
  + 
  13. 
  Additional 
  counts 
  will 
  be 
  found 
  in 
  table 
  1. 
  

  

  Coloration. 
  — 
  In 
  alcohol, 
  straw-colored 
  with 
  silvery 
  lateral 
  band, 
  bor- 
  

   dered 
  above 
  by 
  a 
  narrow 
  dark 
  streak, 
  wider 
  anteriorly 
  ; 
  middorsal 
  line 
  

   with 
  a 
  prominent 
  row 
  of 
  black 
  pigment 
  spots 
  or 
  cells; 
  each 
  scale 
  of 
  

   back 
  above 
  silvery 
  lateral 
  band 
  with 
  a 
  black 
  spot, 
  some 
  scales 
  with 
  two 
  

   of 
  these 
  small 
  pigment 
  spots, 
  thus 
  making 
  two 
  rows 
  of 
  spots 
  each 
  side 
  

   of 
  middorsal 
  line 
  ; 
  tip 
  of 
  snout 
  with 
  black 
  pigment 
  ; 
  a 
  few 
  black 
  pig- 
  

   ment 
  cells 
  on 
  sides 
  of 
  lower 
  jaw 
  and 
  a 
  few 
  near 
  its 
  tip. 
  

  

  Remarks. 
  — 
  This 
  new 
  species 
  differs 
  from 
  all 
  other 
  atherinids 
  in 
  

   having 
  four 
  glandlike 
  depressions 
  on 
  the 
  dorsal 
  surface 
  of 
  the 
  snout 
  

   with 
  the 
  exception 
  of 
  species 
  referred 
  to 
  Thyrinops 
  and 
  Membras. 
  

   However, 
  in 
  the 
  species 
  of 
  the 
  latter 
  genus 
  the 
  anus 
  is 
  only 
  a 
  short 
  dis- 
  

   tance 
  in 
  front 
  of 
  the 
  anal 
  origin 
  and 
  the 
  margins 
  of 
  the 
  scales 
  are 
  usu- 
  

   ally 
  strongly 
  crenulate, 
  whereas 
  in 
  the 
  Adenops 
  analis 
  the 
  anus 
  is 
  far 
  

   forward 
  and 
  the 
  margins 
  of 
  the 
  scales 
  are 
  entire. 
  

  

  Named 
  analis 
  in 
  reference 
  to 
  the 
  position 
  of 
  the 
  anus. 
  

  

  ADENOPS 
  ARGENTEUS, 
  new 
  species 
  

  

  FiGUEE 
  7 
  

  

  Holotype. 
  — 
  U. 
  S. 
  N. 
  M. 
  No. 
  121848, 
  a 
  specimen, 
  42.5 
  mm. 
  in 
  standard 
  

   length, 
  taken 
  by 
  the 
  Albatross 
  at 
  Sabanilla, 
  Colombia, 
  March 
  16-22, 
  

   1884. 
  

  

  Paratype. 
  — 
  ^U. 
  S. 
  N. 
  M. 
  No. 
  121849, 
  a 
  specimen, 
  41.7 
  mm. 
  in 
  standard 
  

   length, 
  bearing 
  same 
  data 
  as 
  the 
  holotype. 
  

  

  Description. 
  — 
  Detailed 
  measurements 
  were 
  made 
  on 
  the 
  holotype 
  and 
  

   paratype, 
  and 
  these 
  data 
  are 
  recorded 
  in 
  table 
  1. 
  

  

  Greatest 
  depth 
  about 
  5, 
  head 
  4i/4, 
  both 
  in 
  standard 
  length 
  ; 
  snout 
  3i/^, 
  

   orbit 
  31/5, 
  interorbital 
  2% 
  to 
  3, 
  all 
  in 
  length 
  of 
  head 
  ; 
  premaxillary 
  a 
  

   little 
  curved, 
  the 
  gape 
  of 
  mouth 
  somewhat 
  concave; 
  mouth 
  small. 
  

   Maxillary 
  not 
  reaching 
  anywhere 
  near 
  front 
  of 
  orbit; 
  gill 
  rakers 
  

   slender, 
  about 
  two-thirds 
  diameter 
  of 
  pupil 
  ; 
  rear 
  margin 
  of 
  pupil 
  at 
  

   middle 
  of 
  length 
  of 
  head; 
  pelvic 
  fin 
  insertions 
  equidistant 
  between 
  

  

  