﻿30 
  PROCEEDINGS 
  OF 
  THE 
  NATIONAL 
  MUSEUM 
  vol. 
  9» 
  

  

  The 
  following 
  vertebral 
  counts 
  were 
  made: 
  T. 
  guija^ 
  one 
  count 
  of 
  

   20+21; 
  T. 
  'pachylepis^ 
  one 
  count 
  20 
  + 
  21; 
  2\ 
  chagresi, 
  two 
  counts 
  

   19 
  + 
  20 
  and 
  19 
  + 
  21; 
  T. 
  meeki, 
  one 
  count 
  20 
  + 
  20; 
  7\ 
  crystallina^ 
  one 
  

   count 
  18+21 
  ; 
  T. 
  colombiensis, 
  one 
  count 
  20 
  + 
  19. 
  

  

  Genus 
  MELANIRIS 
  Meek 
  

  

  Melaniris 
  Meehv, 
  Publ. 
  Field 
  Columbian 
  Mus., 
  zool. 
  ser., 
  vol. 
  3, 
  No. 
  6, 
  p. 
  117, 
  1902 
  

   (genotype: 
  Melaniris 
  balsanus 
  Meek). 
  

  

  The 
  diagnosis 
  of 
  this 
  genus 
  was 
  based 
  on 
  10 
  paratypes 
  of 
  Melaniris 
  

   balsanus, 
  U. 
  S. 
  N. 
  M. 
  No. 
  55793, 
  from 
  Rio 
  Balsas, 
  Balsas, 
  Mexico. 
  I 
  

   remove 
  this 
  species 
  from 
  Thyrina 
  as 
  recognized 
  by 
  Jordan 
  and 
  Hubbs 
  

   in 
  their 
  1919 
  review 
  on 
  the 
  basis 
  of 
  the 
  lower 
  jaws 
  being 
  equal 
  to 
  or 
  

   a 
  little 
  longer 
  than 
  upper, 
  instead 
  of 
  shorter 
  as 
  in 
  Thyrinops, 
  and 
  

   on 
  the 
  few 
  number 
  of 
  abdominal 
  vertebrae 
  — 
  15 
  or 
  16 
  instead 
  of 
  18 
  to 
  

   20. 
  The 
  ascending 
  premaxillary 
  process 
  of 
  Melaniris 
  is 
  broad-based 
  

   and 
  triangular 
  in 
  shape 
  whereas 
  in 
  Thyrinops 
  it 
  is 
  narrower 
  based, 
  

   longer, 
  and 
  slenderer, 
  and 
  I 
  find 
  no 
  glandlike 
  structures 
  on 
  top 
  of 
  

   snout 
  as 
  in 
  Thyrinops. 
  The 
  abdominal 
  cavity 
  extends 
  to 
  opposite 
  the 
  

   base 
  of 
  the 
  second 
  branched 
  anal 
  ray 
  of 
  Melaniris 
  and 
  notably 
  farther 
  

   posteriorly 
  in 
  Thyrinops. 
  

  

  Genus 
  CHIROSTOMA 
  Swainson 
  

  

  Chirostoma 
  Swainson, 
  The 
  natural 
  history 
  and 
  classification 
  of 
  fishes, 
  amphib- 
  

   ians 
  and 
  reptiles, 
  or 
  monocardian 
  animals, 
  vol. 
  2, 
  p. 
  243, 
  fig. 
  67, 
  1839 
  (geno- 
  

   type: 
  Atherina 
  humboldtiana 
  Cuvier 
  and 
  Valenciennes). 
  

  

  dtherinoides 
  Bleeker, 
  Verb. 
  Batav. 
  Gen. 
  (Japan), 
  vol. 
  25, 
  p. 
  40, 
  1853 
  (genotype: 
  

   Atherina 
  humboldtiana 
  Cuvier 
  and 
  Valenciennes). 
  

  

  Atheronichthys 
  Bleekeb, 
  ibid., 
  p. 
  41, 
  1853 
  (genotype: 
  Atherina 
  vomerina 
  Cuvier 
  

   and 
  Valenciennes 
  =(?. 
  humboldtiana). 
  

  

  Beterognathus 
  Gikaed, 
  Proc. 
  Acad. 
  Nat. 
  Sci. 
  Philadelphia, 
  vol. 
  7, 
  p. 
  198, 
  1854 
  

   (genotype: 
  Atherina 
  humboldtiana 
  Cuvier 
  and 
  Valenciennes). 
  

  

  Lethostole 
  Jokdan 
  and 
  Eveemann, 
  U. 
  S. 
  Nat. 
  Mus. 
  Bull. 
  47, 
  pt. 
  1, 
  p. 
  792, 
  1896 
  

   (genotype: 
  Chirostoma 
  estor 
  Jordan). 
  

  

  Elopsarum 
  Jordan 
  and 
  Evtrmann, 
  Kept. 
  U. 
  S. 
  Fish 
  Comm. 
  for 
  1895, 
  p. 
  330, 
  1896 
  

   (genotype: 
  Chirostoma 
  jordani 
  Woolman). 
  

  

  Atherinichthys 
  Bleeker, 
  in 
  Jordan, 
  Genera 
  of 
  fishes, 
  pt. 
  2, 
  p. 
  253, 
  1919 
  (emended 
  

   spelling), 
  

  

  Charalia 
  De 
  Buen, 
  Ann. 
  Inst. 
  Biol. 
  Mex., 
  vol. 
  16, 
  No. 
  2, 
  p. 
  505, 
  1945 
  (genotype: 
  

   Chirostoma 
  bartoni 
  Jordan 
  and 
  Evermann). 
  

  

  Palmichthys 
  De 
  Buen, 
  ibid., 
  p. 
  527 
  (genotype: 
  Chirostoma 
  diazi 
  Jordan 
  and 
  

   Snyder). 
  

  

  Acotlanichthys 
  De 
  Buen, 
  ibid., 
  p. 
  526 
  (genotype: 
  Chirostoma 
  sphyraena 
  Bou- 
  

   lenger). 
  

  

  Otalia 
  De 
  Buen, 
  ibid., 
  p. 
  528 
  (genotype: 
  Chirostoma 
  promelas 
  Jordan 
  and 
  

   Snyder). 
  

  

  Jordan 
  and 
  Hubbs 
  (1919) 
  and 
  Jordan 
  (Z. 
  c, 
  1919) 
  have 
  interchanged 
  

   the 
  genotypes 
  for 
  Bleeker 
  's 
  genera 
  Atherinoides 
  and 
  Atheronichthys, 
  

   but 
  I 
  have 
  corrected 
  this 
  in 
  the 
  synonymy 
  above. 
  

  

  