﻿[39] 
  DEVELOPMENT 
  OF 
  THE 
  CETACEA. 
  465 
  

  

  on 
  the 
  side 
  of 
  the 
  neck 
  to 
  the 
  anterior 
  dorsal 
  region, 
  and 
  is 
  lost 
  in 
  the 
  

   combined 
  longissimus 
  and 
  spinalis 
  dorsi. 
  Where 
  the 
  body 
  begins 
  to 
  

   taper 
  behind 
  a 
  division 
  of 
  the 
  two 
  latter 
  is 
  perceptible. 
  Hereabouts 
  a 
  

   superficial 
  tendon 
  passes 
  obliquely 
  upwards 
  and 
  backwards 
  from 
  the 
  

   outer 
  longissimus 
  to 
  the 
  inner 
  spinalis. 
  A 
  little 
  way 
  behind, 
  another 
  

   bridge 
  of 
  two 
  oblique 
  tendons 
  similarly 
  crosses, 
  and 
  immediately 
  pos- 
  

   terior 
  to 
  this 
  five 
  more, 
  which 
  together 
  unite 
  into 
  a 
  strong 
  cord, 
  wrapped 
  

   one 
  within 
  the 
  other. 
  Meanwhile 
  from 
  each 
  muscle 
  there 
  is 
  continued 
  

   posteriorly, 
  quite 
  to 
  the 
  end 
  of 
  the 
  spinal 
  column, 
  a 
  single, 
  thick, 
  mas- 
  

   sive 
  tendon. 
  Besides 
  the 
  foregoing, 
  both 
  longissimus 
  and 
  spinalis 
  dorsi 
  

   possess 
  a 
  deep 
  series 
  of 
  long, 
  narrow 
  tendons, 
  one 
  to 
  each 
  vertebra, 
  but 
  

   mingled 
  together 
  by 
  interstitial 
  fleshy 
  fibers. 
  It 
  results 
  that 
  these 
  dor- 
  

   sal 
  muscles 
  act 
  upon 
  every 
  vertebra 
  independently, 
  whilst 
  at 
  the 
  same 
  

   time 
  the 
  motor 
  power 
  of 
  the 
  fibrocartilaginous 
  tail 
  is 
  derived 
  from 
  the 
  

   lengthened 
  and 
  more 
  powerful 
  cords, 
  for 
  from 
  these 
  there 
  extends 
  back- 
  

   wards 
  a 
  firm, 
  glistening 
  fascia, 
  spread 
  over 
  and 
  incorporated 
  with 
  the 
  

   deep 
  tail 
  substance. 
  

  

  "Supra 
  caudal. 
  The 
  single 
  muscle 
  (or 
  compound 
  muscle, 
  if 
  so 
  re- 
  

   garded) 
  to 
  which 
  I 
  give 
  this 
  appellation 
  lies 
  external 
  to 
  the 
  last, 
  along 
  

   the 
  narrow 
  portion 
  of 
  the 
  caudal 
  vertebrae 
  and 
  on 
  the 
  upper 
  side 
  of 
  the 
  

   transverse 
  process, 
  narrow 
  in 
  front, 
  where 
  fleshy, 
  it 
  widens 
  somewhat 
  

   and 
  forms 
  a 
  tolerably 
  thick 
  fusiform 
  belly, 
  which 
  again 
  flattens 
  and 
  be- 
  

   comes 
  tendinous. 
  In 
  its 
  course 
  it 
  is 
  attached 
  partly 
  to 
  the 
  vertebral 
  

   bodies 
  and 
  partly 
  to 
  the 
  transverse 
  processes, 
  sending 
  off 
  a 
  special 
  ten- 
  

   don 
  to 
  each 
  of 
  the 
  latter. 
  Posteriorly 
  the 
  flattened 
  tendon 
  lies 
  against 
  

   the 
  sides 
  of 
  the 
  bodies 
  of 
  the 
  terminal 
  vertebrae, 
  and 
  ultimately 
  is 
  lost 
  

   in 
  the 
  general 
  expansion 
  of 
  the 
  upper 
  surface 
  of 
  the 
  tail 
  flukes. 
  

  

  " 
  Coming 
  under 
  the 
  denomination 
  of 
  multifidus 
  spinas 
  and 
  rotatores 
  

   spinas, 
  because 
  of 
  their 
  position, 
  origins, 
  and 
  insertions, 
  are 
  a 
  great 
  number 
  

   of 
  musculotendinous 
  bundles, 
  very 
  apparent 
  and 
  well 
  marked, 
  but 
  diffi- 
  

   cult 
  individually 
  to 
  separate 
  and 
  define. 
  These 
  are 
  still 
  more 
  numerous 
  

   and 
  closely 
  packed 
  together 
  in 
  Lagenorhynchus 
  than 
  in 
  Globiocephalus, 
  

   in 
  consequence 
  of 
  the 
  number 
  and 
  approximation 
  of 
  the 
  vertebrae 
  in 
  the 
  

   former. 
  Stannius 
  recognizes 
  such 
  a 
  deep 
  set 
  of 
  muscles 
  in 
  the 
  porpoise; 
  

   and 
  I 
  can 
  corroborate 
  his 
  observation 
  in 
  that 
  genus. 
  Their 
  general 
  ar- 
  

   rangement 
  is 
  by 
  tendons 
  from 
  the 
  dorsal 
  metapophyses, 
  and 
  trending 
  

   forwards 
  and 
  inwards 
  are 
  attached 
  muscularly 
  to 
  the 
  sides 
  of 
  the 
  roots 
  

   of 
  the 
  spinous 
  process 
  in 
  advance 
  of 
  their 
  origin. 
  The 
  most 
  anterior 
  

   one 
  is 
  fixed 
  to 
  the 
  atlas. 
  

  

  " 
  But 
  there 
  are 
  besides 
  a 
  deeper 
  layer 
  of 
  fascicles 
  springing 
  tendin- 
  

   ously 
  from 
  the 
  spines 
  and 
  dorsal 
  arches, 
  and 
  these 
  becoming 
  fleshy 
  are 
  

   inserted 
  into 
  the 
  transverse 
  processes 
  of 
  the 
  same 
  vertebrae, 
  doubtless 
  

   semispinales 
  ,as 
  Stannius* 
  names 
  them 
  in 
  Phocccna. 
  He 
  alludes, 
  more- 
  

   over, 
  to 
  another 
  set 
  of 
  fasciculi, 
  close 
  to 
  the 
  last, 
  and 
  connected 
  with 
  

   the 
  vertebral 
  processes, 
  but 
  he 
  has 
  not 
  named 
  them. 
  

  

  * 
  " 
  Muskeln 
  des 
  Tiimmlers," 
  Muller's 
  Archiv, 
  1349, 
  p. 
  30. 
  

   S. 
  Mis. 
  70 
  30 
  

  

  