﻿846 
  REPORT 
  OF 
  COMMISSIONER 
  OF 
  FISH 
  AND 
  FISHERIES. 
  [58] 
  

  

  191.— 
  GASTROSTOMUS 
  ' 
  Gill 
  & 
  Ryder. 
  

   649. 
  Gastrostomus 
  bairdii 
  Gill 
  & 
  Ryder. 
  B. 
  

  

  Order 
  U.— 
  OPISTHOMI. 
  (P) 
  

  

  Family 
  LXVI.— 
  PTILICHTHYID^. 
  2 
  (56 
  &.) 
  

   192.— 
  PTILICHTHYS 
  Beau. 
  (179) 
  

  

  650. 
  Ptilichthys 
  goodei 
  Beau. 
  A. 
  (594.) 
  

  

  Family 
  LXYIL— 
  KOTACANTHID^. 
  

   193— 
  NOTACANTHUS 
  Bloch. 
  (180) 
  

  

  651. 
  Notacanthus 
  chemnitzi 
  Bloch. 
  G. 
  B. 
  (595) 
  

  

  652. 
  Notacanthus 
  phasganorus 
  Goode, 
  B. 
  (595/.) 
  

  

  653. 
  Notacanthus 
  analis 
  3 
  Gill. 
  B. 
  

  

  of 
  the 
  two 
  suspensorial 
  bones, 
  with 
  minute 
  teeth 
  in 
  both 
  jaws, 
  with 
  a 
  short 
  abdomen 
  

   and 
  long, 
  attenuated 
  tail, 
  branchial 
  apertures 
  narrow 
  and 
  very 
  far 
  behind, 
  dorsal 
  

   and 
  aual 
  fins 
  continued 
  nearly 
  to 
  the 
  end 
  of 
  the 
  tail, 
  and 
  minute 
  pectoral 
  fins. 
  

  

  " 
  The 
  mandibular 
  rami 
  are 
  exceedingly 
  narrow 
  and 
  slender, 
  but 
  the 
  jaws 
  are 
  ex- 
  

   tremely 
  expansible 
  and 
  the 
  skin 
  is 
  correspondingly 
  dilatable, 
  consequently 
  an 
  enor- 
  

   mous 
  pouch 
  may 
  be 
  developed. 
  Inasmuch 
  as 
  the 
  slenderness 
  and 
  fragility 
  of 
  the 
  

   jaws 
  aud 
  the 
  absence 
  of 
  raptatorial 
  teeth 
  preclude 
  the 
  idea 
  of 
  the 
  species 
  being 
  true 
  

   fishes 
  of 
  prey, 
  it 
  is 
  probable 
  that 
  they 
  may 
  derive 
  their 
  food 
  from 
  the 
  water 
  which 
  

   is 
  received 
  into 
  the 
  pouch 
  by 
  a 
  process 
  of 
  selection 
  of 
  the 
  small 
  or 
  minute 
  organisms 
  

   therein 
  contained." 
  The 
  skin 
  of 
  the 
  pouch 
  has 
  a 
  peculiar 
  velvety 
  appearance, 
  like 
  

   the 
  wing 
  membraue 
  of 
  a 
  bat. 
  Two 
  species 
  are 
  known, 
  provisionally 
  referred 
  to 
  two 
  

   genera, 
  Eurypharynx 
  pelecanoides 
  Vaillaut 
  and 
  Gastrostomus 
  bairdii. 
  Both 
  are 
  from 
  

   great 
  depths 
  in 
  the 
  sea, 
  the 
  former 
  having 
  been 
  taken 
  by 
  the 
  " 
  Travailleur," 
  in 
  1882, 
  

   off 
  the 
  coast 
  of 
  Morocco. 
  

  

  (Eurypharyngidas 
  Gill 
  & 
  Ryder, 
  Proc. 
  U. 
  S. 
  Nat. 
  Mus., 
  1883, 
  264.) 
  

   1 
  Gastrostomus 
  Gill 
  & 
  Ryder. 
  

  

  Gill 
  & 
  Ryder, 
  Proc. 
  U. 
  S. 
  Nat. 
  Mus., 
  1883, 
  271 
  ; 
  type 
  Gastrostomus 
  bairdii 
  G. 
  & 
  R. 
  

  

  This 
  genus 
  is 
  supposed 
  to 
  be 
  distinguished 
  from 
  Eurypharynx 
  by 
  the 
  following 
  char- 
  

   acters: 
  Cranium 
  short, 
  nearly 
  as 
  broad 
  as 
  long 
  ; 
  dentigerous 
  bones 
  almost 
  seven 
  times 
  

   length 
  of 
  cranium 
  ; 
  jaws 
  with 
  miuute, 
  acute, 
  conic 
  teeth 
  depressed 
  inwards, 
  in 
  a 
  very 
  

   narrowband; 
  no 
  enlarged 
  teeth 
  at 
  tip 
  of 
  mandible; 
  tail 
  with 
  a 
  rayless 
  membrane 
  

   under 
  its 
  tip. 
  (radrr/p, 
  stomach 
  ; 
  drojua, 
  mouth.) 
  

  

  {Gastrostomus 
  bairdii 
  Gill 
  & 
  Ryder, 
  1. 
  c, 
  lb83, 
  271. 
  Gulf 
  Stream, 
  lat. 
  40°, 
  in 
  deep 
  

   water.) 
  

  

  Eurypharynx 
  pelecanoides 
  (Vaillant, 
  Coinptes 
  Rendus 
  Acad. 
  Sci. 
  Paris, 
  1882, 
  1232) 
  is 
  

   supposed 
  to 
  differ 
  iu 
  having 
  the 
  "cranium 
  prolonged 
  backwards, 
  the 
  dentigerous 
  

   bones 
  little 
  more 
  than 
  thi-ee 
  times 
  as 
  long 
  as 
  the 
  cranium 
  ; 
  faint 
  dentary 
  granulations 
  

   on 
  both 
  jaws 
  and 
  at 
  the 
  extremity 
  of 
  the 
  mandible 
  two 
  hooked 
  teeth; 
  the 
  tail 
  end- 
  

   ing 
  in 
  a 
  point." 
  It 
  is 
  not 
  uulikely 
  that 
  the 
  two 
  species 
  may 
  prove 
  identical. 
  

  

  2 
  It 
  is 
  almost 
  certain 
  that 
  Ptilichthys 
  has 
  little 
  relation 
  to 
  the 
  Mastacembelidat. 
  It 
  

   should 
  probably 
  be 
  regarded 
  as 
  a 
  distinct 
  family, 
  Ptilichthyidce, 
  but 
  whether 
  this 
  fam- 
  

   ily 
  belongs 
  to 
  the 
  Opisthomi 
  or 
  to 
  the 
  Acanthopteri 
  cannot 
  be 
  ascertained 
  without 
  ex- 
  

   amination 
  of 
  the 
  skeleton. 
  

  

  z 
  Notacanthus 
  analis 
  Gill. 
  Proc. 
  U. 
  S. 
  Nat. 
  Mus. 
  1883, 
  255. 
  Gulf 
  Stream, 
  latitude 
  

   40'' 
  at 
  a 
  depth 
  of 
  548 
  fathoms. 
  

  

  