﻿586 
  REPORT 
  OF 
  COMMISSIONER 
  OF 
  FISH 
  AND 
  FISHERIES. 
  [98] 
  

  

  EXPLANATION 
  OF 
  PLATE 
  XXI. 
  

   Clupea 
  sapidissima. 
  (The 
  Common 
  Shad.) 
  

  

  Fig. 
  145. 
  Cross-section 
  through 
  the 
  region 
  of 
  the 
  eyes 
  of 
  an 
  emhryo 
  ten 
  days 
  old; 
  

  

  bb 
  basibranchial, 
  cli 
  ceratohyal, 
  ME 
  Meckel's 
  cartilage, 
  pt 
  palatine, 
  Tr 
  trabecule 
  

  

  cranii, 
  E 
  eye, 
  Mb 
  mid-brain, 
  Cer 
  cerebrum. 
  

   Fig. 
  146. 
  Cross-section 
  through 
  the 
  anterior 
  part 
  of 
  the 
  auditory 
  region 
  of 
  the 
  same 
  

  

  embryo 
  ; 
  au 
  auditory 
  vesicle 
  with 
  acoustic 
  macula 
  or 
  end 
  organ 
  in 
  its 
  lower 
  

  

  wall, 
  Mo 
  medulla 
  oblongata, 
  Ch 
  chorda, 
  Hm 
  upper 
  eud 
  of 
  hyomandibular, 
  i, 
  ii, 
  ill, 
  

  

  and 
  iv 
  branchial 
  arches, 
  pa 
  parachordal 
  cartilages. 
  

   Fig. 
  147. 
  Cross-section 
  through 
  the 
  posterior 
  part 
  of 
  the 
  auditory 
  region 
  of 
  the 
  same; 
  

  

  lettering 
  the 
  same, 
  except 
  that 
  the 
  basibranchial 
  bar 
  bb 
  is 
  cut 
  through, 
  as 
  well 
  

  

  as 
  the 
  whole 
  five 
  branchial 
  arches, 
  also 
  the 
  auditory 
  canals 
  and 
  vestibule 
  of 
  the 
  

  

  membranous 
  labyrinth. 
  

  

  