﻿702 
  REPORT 
  OF 
  COMMISSIONER 
  OF 
  FISH 
  AND 
  FISHERIES. 
  [4] 
  

  

  § 
  Lamjpetra 
  Gray. 
  (3j>t) 
  

  

  5. 
  AmrnoctEtes 
  cibarius 
  1 
  Guard. 
  C. 
  Ana. 
  (7) 
  

  

  6. 
  Ammocoetes 
  aureus 
  Bean. 
  A. 
  Aua. 
  (7l>) 
  

  

  § 
  Ammoccetc8. 
  

  

  7. 
  Ainmocoetes 
  cepypterus 
  2 
  Abbott. 
  Vn. 
  (8) 
  

  

  5.-PETROMYZON 
  (Artedi) 
  Linnams. 
  (7) 
  

   $ 
  Ichihyomyzon 
  Girard. 
  (G) 
  

  

  8. 
  Petromyzon 
  bdellium 
  3 
  Jordan. 
  Vn. 
  (0) 
  

  

  9. 
  Petromyzon 
  hirudo 
  Girard. 
  Vn. 
  (\)b.) 
  

  

  10. 
  Petromyzon 
  castaneus 
  Girard. 
  Vw. 
  (10) 
  

  

  § 
  Petromyzon. 
  (7) 
  

  

  11. 
  Petromyzon 
  marinus 
  L. 
  N. 
  Eu. 
  Ana. 
  (11) 
  

   lib 
  Petromyzon 
  marinus 
  dorsatus 
  Wilder. 
  Ve. 
  (12) 
  

  

  6.— 
  BATHYMYZON 
  ' 
  Gill. 
  

  

  12. 
  Bathymyzon 
  bairdii 
  5 
  Gill. 
  B. 
  

  

  Class 
  III.— 
  PISCES. 
  

   Subclass 
  Elasmobkanchii. 
  

  

  Order 
  D.— 
  OPISTHARTHRI. 
  6 
  

  

  Family 
  V.— 
  NOTIDANID^. 
  (15) 
  

  

  7.— 
  HEPTRANCHIAS 
  Ralinesque. 
  (32) 
  

   § 
  Notorhynchus 
  Ayres. 
  

  

  13. 
  Heptranchias 
  maculatus 
  Ayres. 
  C. 
  (42) 
  

  

  8.-HEXANCHUS 
  Ralinesque. 
  (316.) 
  

  

  14. 
  Hesarrchus 
  corinus 
  Jordan 
  & 
  Gilbert. 
  C. 
  (42/j.) 
  

  

  1 
  The 
  name 
  Petromyzon 
  plumoeus 
  is 
  preoccupied 
  by 
  Shaw, 
  1805. 
  

  

  s 
  The 
  name 
  Petromyzon 
  niger 
  is 
  preoccupied 
  by 
  Lacdpcdc, 
  1798. 
  This 
  is 
  probably 
  

   the 
  species 
  poorly 
  described 
  by 
  Abbott 
  as 
  Amm. 
  apyptera. 
  

  

  •''The 
  name 
  Petromyzon 
  argenteus 
  is 
  preoccupied 
  by 
  Bloch, 
  17'.)0. 
  I 
  propose 
  the 
  new 
  

   name 
  P. 
  bdellium 
  for 
  this 
  species, 
  as 
  I 
  cannot 
  identify 
  it 
  certainly 
  with 
  Ammocoetes 
  

   concolor 
  Kir 
  tl 
  and, 
  A. 
  borcalis 
  Ag., 
  or 
  any 
  other 
  nominal 
  species, 
  based 
  on 
  larval 
  forms. 
  

  

  ♦Bathymyzon 
  Gill, 
  Proc. 
  U. 
  S. 
  Nat. 
  Mas., 
  1883, 
  254; 
  typo 
  Petromyzon 
  (Bathymyzon\ 
  

   bairdii 
  Gill. 
  (fiaQvS 
  — 
  deep 
  ; 
  /.iv^go 
  — 
  to 
  suck.) 
  This 
  genus 
  is 
  said 
  to 
  differ 
  from 
  Petro- 
  

   myzon 
  in 
  having 
  " 
  the 
  suproral 
  and 
  infroral 
  plates 
  or 
  lamina; 
  destitute 
  of 
  odontoid, 
  

   tubercles, 
  the 
  armature 
  of 
  the 
  lamprey 
  type 
  being 
  obsolescent." 
  

  

  6 
  Petromyzon 
  {Bathymyzon) 
  bairdii 
  Gill., 
  1. 
  c. 
  254, 
  Gulf 
  Stream, 
  latitude 
  40°, 
  at 
  a 
  depth 
  

   of 
  547 
  fathoms. 
  The 
  species 
  has 
  not 
  been 
  described, 
  except 
  that 
  it 
  is 
  " 
  closely 
  related 
  

   to 
  Petromyzon 
  marinus." 
  

  

  6 
  The 
  groups 
  called 
  Opistharthri 
  and 
  Proarihri, 
  certainly 
  worthy 
  of 
  ordinal 
  distino* 
  

   tion 
  from 
  the 
  other 
  Sharksj 
  are 
  defined 
  by 
  Professor 
  Gill 
  in 
  our 
  Synopsis 
  Fish, 
  N, 
  A<* 
  

   967. 
  

  

  