﻿.508 
  REPORT 
  OF 
  COMMISSIONER 
  OF 
  FISH 
  AND 
  FISHERIES. 
  [20] 
  

  

  parent 
  surface 
  of 
  the 
  latter. 
  The 
  embryonic 
  axis 
  shows 
  the 
  segments 
  

   or 
  somites 
  m, 
  distinctly 
  developed, 
  but 
  it 
  is 
  very 
  remarkable 
  that 
  the 
  

   segmentation 
  does 
  not 
  end 
  at 
  the 
  point 
  where 
  the 
  axis 
  of 
  the 
  embryo, 
  

   thus 
  far 
  developed, 
  ends. 
  The 
  right 
  and 
  left 
  limbs 
  of 
  the 
  blastodermic 
  

   rim, 
  or 
  lips 
  of 
  the 
  blastopore, 
  form 
  a 
  A-shaped 
  mass, 
  together 
  with 
  the 
  

   embryonic 
  batly 
  anteriorly; 
  but, 
  unlike 
  any 
  other 
  normal 
  Teleostean 
  

   embryo, 
  both 
  the 
  diverging 
  limbs 
  of 
  the 
  rim 
  of 
  the 
  blastoderm 
  show 
  

   distinct 
  indications 
  of 
  metameric 
  segmentation 
  at 
  m, 
  and 
  behind 
  the 
  

   point 
  where 
  concrescence 
  has 
  already 
  taken 
  place. 
  

  

  Just 
  within 
  the 
  yelk 
  and 
  a 
  little 
  in 
  front 
  of 
  the 
  yelk 
  blastopore, 
  which 
  

   runs 
  forward 
  into 
  the 
  acute 
  angle 
  formed 
  by 
  the 
  limbs 
  of 
  the 
  blasto- 
  

   dermic 
  rim 
  br, 
  lies 
  the 
  large 
  oil-drop 
  o. 
  A 
  lozenge 
  shaped 
  mass 
  of 
  cells 
  

   lies 
  in 
  the 
  acute 
  angle 
  of 
  the 
  A 
  shaped 
  terminal 
  part 
  of 
  the 
  embryo, 
  

   which 
  appears 
  to 
  contain 
  or 
  overlie 
  Kupffer's 
  vesicle, 
  Jcv, 
  and 
  what 
  was 
  

   assumed 
  to 
  be 
  the 
  posterior 
  end 
  of 
  the 
  chorda 
  ch 
  at 
  the 
  time 
  the 
  draw- 
  

   ing 
  was 
  made; 
  but 
  of 
  the 
  certainty 
  of 
  this 
  determination 
  I 
  am 
  not 
  at 
  

   present 
  satisfied. 
  I 
  was 
  enabled 
  to 
  sketch 
  this 
  and 
  a 
  slightly 
  more 
  ad- 
  

   vanced 
  stage 
  several 
  times, 
  and, 
  as 
  already 
  stated, 
  I 
  found 
  the 
  same 
  

   condition 
  of 
  things 
  present 
  in 
  a 
  number 
  of 
  embryos, 
  which 
  appeared 
  to 
  

   be 
  developing 
  normally. 
  Four 
  other 
  sketches 
  show 
  that 
  the 
  blasto- 
  

   derm 
  fiually 
  closes 
  very 
  much 
  as 
  in 
  other 
  Teleostean 
  embryos, 
  and 
  that 
  

   pronounced 
  wrinkles 
  radiate 
  from 
  the 
  crater 
  like 
  opening 
  upon 
  the 
  yelk 
  

   where 
  the 
  yelk-blastopore 
  finally 
  closes. 
  

  

  The 
  conclusions 
  of 
  His 
  and 
  Rauber, 
  to 
  the 
  effect 
  that 
  the 
  embryonic 
  

   axis 
  is 
  formed 
  by 
  the 
  gradual 
  fusion 
  from 
  before 
  backwards 
  of 
  the 
  edges 
  

   or 
  lips 
  of 
  the 
  yelk 
  blastopore 
  as 
  it 
  advances 
  over 
  the 
  surface 
  of 
  the 
  vitel- 
  

   line 
  globe, 
  are 
  completely 
  and 
  emphatically 
  confirmed 
  in 
  the 
  case 
  of 
  

   this 
  species. 
  It 
  must 
  be 
  admitted, 
  however, 
  that 
  the 
  presence 
  of 
  the 
  

   cellular 
  mass 
  between 
  the 
  limbs 
  of 
  the 
  blastodermic 
  rim 
  where 
  they 
  

   join 
  the 
  anterior 
  portion 
  of 
  the 
  embryonic 
  body 
  is 
  not 
  a 
  little 
  puzzling. 
  

  

  This 
  species 
  I 
  was 
  enabled 
  to 
  study, 
  through 
  the 
  kind 
  help 
  of 
  Col. 
  M. 
  

   McDonald 
  and 
  Mr. 
  W. 
  P. 
  Sauerhoff, 
  at 
  Cherrystone, 
  Va.. 
  during 
  the 
  

   first 
  week 
  of 
  August, 
  1SS1. 
  

  

  VII.— 
  Siphostoma 
  fuscum 
  (Storer) 
  J. 
  & 
  G. 
  (Common 
  Pipe-fish.) 
  

  

  The 
  earliest 
  noteworthy 
  observations 
  upon 
  the 
  development 
  of 
  any 
  

   species 
  allied 
  to 
  the 
  one 
  here 
  considered, 
  which 
  I 
  have 
  been 
  able 
  to 
  find, 
  

   were 
  recorded 
  by 
  liatkke. 
  37 
  The 
  embryos 
  of 
  a 
  species 
  called 
  Syngnaihus 
  

   argentatus 
  is 
  figured 
  on 
  plate 
  v 
  of 
  Eathke's 
  memoir, 
  and 
  he 
  shows 
  the 
  

   gill 
  clefts 
  exposed 
  or 
  uncovered 
  in 
  the 
  young, 
  a 
  condition 
  not 
  observed 
  

   by 
  later 
  authors. 
  The 
  next 
  memoir 
  in 
  historical 
  order 
  is 
  by 
  A. 
  de 
  

   Quatrefages, 
  and 
  deals 
  with 
  another 
  species, 
  probably 
  another 
  genus, 
  in 
  

   which 
  the 
  eggs 
  are 
  not 
  covered 
  by 
  lateral 
  folds 
  extending 
  down 
  from 
  

  

  37 
  H. 
  Rathke. 
  Zur 
  morphologic; 
  Reisbemerkuugen 
  aus 
  Taurien. 
  4 
  to, 
  pp. 
  192, 
  

   pin. 
  5, 
  Riga 
  and 
  Leipzig, 
  1837. 
  

  

  