﻿204 
  Systematic 
  Position 
  of 
  Maciistium 
  cliavesi. 
  

  

  30.120 
  mm. 
  Onon 
  R. 
  Godeflroy 
  Mua. 
  

  

  31-32. 
  100-105 
  mm. 
  Inland 
  Sea 
  of 
  Japan. 
  R. 
  Gordon 
  Smith, 
  

  

  [Esq. 
  

   33-42. 
  80-100 
  mm 
  Gifu, 
  Mino 
  Prov., 
  Japan. 
  Prof. 
  Mitsukuri. 
  

  

  Ammocwtes 
  branchialis, 
  Linn. 
  

  

  Under 
  this 
  name 
  may 
  be 
  placed 
  a 
  number 
  of 
  larvae, 
  most 
  

   of 
  which 
  probably 
  pertain 
  to 
  Lampetra, 
  but 
  some 
  to 
  other 
  

   Petromyzonids. 
  

  

  XIX. 
  — 
  On 
  the 
  Systematic 
  Position 
  of 
  Macristium 
  cliavesi. 
  

   By 
  C. 
  Tate 
  Regan; 
  M.A. 
  

  

  In 
  1903 
  (Ann. 
  & 
  Mag. 
  Nat. 
  Hist. 
  (7) 
  xii. 
  p. 
  345) 
  1 
  described 
  

   a 
  remarkable 
  fish 
  from 
  the 
  Azores, 
  to 
  which 
  I 
  gave 
  the 
  name 
  

   Macristium 
  ckavesi. 
  Recently, 
  when 
  working 
  at 
  the 
  osteology 
  

   and 
  classification 
  of 
  the 
  Iniomi, 
  it 
  seemed 
  to 
  me 
  desirable 
  to 
  

   re-examine 
  this 
  fish 
  ; 
  I 
  accordingly 
  wrote 
  to 
  Major 
  F. 
  A. 
  

   Chaves, 
  who 
  has 
  kindly 
  sent 
  me 
  the 
  specimen. 
  

  

  The 
  type 
  of 
  Macristium 
  chavesi 
  measures 
  110 
  mm. 
  to 
  the 
  

   base 
  of 
  the 
  caudal 
  fin 
  ; 
  it 
  has 
  been 
  a 
  good 
  deal 
  damaged, 
  and 
  

   in 
  the 
  absence 
  of 
  precise 
  information 
  I 
  should 
  judge 
  that 
  it 
  

   may 
  have 
  been 
  washed 
  ashore. 
  The 
  snout 
  and 
  the 
  end 
  of 
  

   the 
  lower 
  jaw 
  are 
  injured 
  and 
  the 
  prsemaxillaries 
  have 
  been 
  

   lost; 
  one 
  of 
  the 
  pectoral 
  fins 
  is 
  complete, 
  but 
  none 
  of 
  the 
  

   other 
  fins 
  has 
  even 
  a 
  single 
  ray 
  entire. 
  

  

  Originally 
  I 
  believed 
  that 
  Macristium 
  was 
  related 
  to 
  

   Bathysaurus, 
  Giinth., 
  which 
  it 
  resembles 
  in 
  the 
  position 
  of 
  

   the 
  fins 
  and 
  the 
  number 
  of 
  rays. 
  I 
  am 
  now 
  of 
  the 
  opinion 
  

   that 
  this 
  resemblance 
  is 
  misleading, 
  for 
  I 
  think 
  that 
  in 
  all 
  

   probability 
  the 
  preemaxillaries 
  would 
  not 
  exclude 
  the 
  max- 
  

   illaiies 
  from 
  the 
  gape. 
  In 
  any 
  case, 
  Macristium 
  must 
  be 
  

   made 
  the 
  type 
  of 
  a 
  distinct 
  family, 
  Macristiidre, 
  probably 
  

   related 
  to 
  the 
  Alepocephalida?. 
  

  

  Before 
  returning 
  the 
  fish 
  to 
  the 
  Ponta 
  Delgada 
  Museum 
  it 
  

   seems 
  to 
  me 
  best 
  to 
  make 
  a 
  figure 
  of 
  it 
  and 
  to 
  reinforce 
  my 
  

   original 
  description. 
  

  

  The 
  body 
  is 
  elongate, 
  moderately 
  compressed, 
  naked 
  ; 
  the 
  

  

  