﻿484 
  REPORT 
  OF 
  COMMISSIONER 
  OF 
  FISH 
  AND 
  FISHERIES. 
  [58] 
  

  

  15. 
  The 
  direction 
  of 
  the 
  axis 
  of 
  the 
  bones 
  of 
  the 
  cms, 
  when 
  developed, 
  

   towards 
  and 
  in 
  a 
  line 
  with 
  the 
  pes 
  in 
  swimming, 
  in 
  both 
  pinnipeds 
  and 
  

   cetaceans. 
  

  

  16. 
  The 
  direction 
  of 
  the 
  axis 
  of 
  the 
  rudimentary 
  femur 
  in 
  Ralithe- 
  

   rium, 
  and 
  the 
  tibia 
  in 
  Balcena, 
  towards 
  the 
  flukes. 
  

  

  17. 
  The 
  presence 
  of 
  a 
  supposed 
  free 
  rudiment 
  of 
  the 
  tail 
  in 
  the 
  foetus 
  

   of 
  the 
  manatee, 
  which 
  is 
  exserted 
  beyond 
  the 
  flukes. 
  

  

  18. 
  The 
  effect 
  of 
  the 
  translocation 
  of 
  the 
  paired 
  limbs 
  as 
  observed 
  in 
  

   other 
  types, 
  especially 
  as 
  indicating 
  that 
  the 
  outgrowth 
  of 
  the 
  limb 
  

   folds 
  in 
  advance 
  of 
  or 
  behind 
  their 
  original 
  or 
  archaic 
  site 
  is 
  influenced 
  

   by 
  heredity, 
  which 
  acts 
  more 
  powerfully 
  through 
  immediate 
  than 
  

   through 
  remote 
  ancestry, 
  in 
  this 
  as 
  in 
  many 
  other 
  cases. 
  

  

  EXPLANATION 
  OF 
  PLATE 
  I. 
  

  

  Reference 
  letters: 
  a, 
  anus; 
  b, 
  blow-bole 
  or 
  holes; 
  cl, 
  clitoris; 
  d, 
  dorsal 
  fin; 
  e, 
  external 
  

   auditory 
  meatus; 
  /, 
  flipper, 
  or 
  fore 
  limb 
  ; 
  h, 
  lateral 
  fluke 
  folds 
  or 
  outward 
  rudiments 
  

   of 
  pedes; 
  m, 
  mouth, 
  in 
  Fig. 
  8; 
  p, 
  penis; 
  u, 
  umbilical 
  cord 
  or 
  navel-string. 
  

  

  Fig. 
  1. 
  Female 
  foetus 
  of 
  Iihachianectes 
  f/laucus, 
  or 
  California 
  gray 
  whale, 
  natural 
  

   size, 
  seen 
  from 
  the 
  side, 
  showing 
  the 
  distribution 
  of 
  the 
  follicles 
  for 
  the 
  vibrissas 
  on 
  the 
  

   snout 
  above 
  and 
  below 
  the 
  cleft 
  of 
  the 
  mouth 
  (N. 
  M. 
  Coll.). 
  

  

  Fig. 
  2. 
  Head 
  of 
  the 
  same, 
  seen 
  from 
  the 
  front, 
  showing 
  the 
  separated 
  blow-holes 
  

   and 
  the 
  follicles 
  for 
  vibrissas 
  between 
  the 
  nostrils 
  and 
  the 
  tip 
  of 
  the 
  snout. 
  

  

  Fig. 
  3. 
  Sketch 
  of 
  the 
  perineal 
  region 
  of 
  the 
  same, 
  as 
  seen 
  from 
  below, 
  showing 
  the 
  

   anus, 
  the 
  vulva 
  behind 
  the 
  clitoris, 
  and 
  the 
  very 
  minute 
  mammary 
  fossae 
  or 
  clefts 
  

   on 
  either 
  side 
  of 
  the 
  latter. 
  

  

  Fig. 
  4. 
  The 
  tail 
  of 
  the 
  same, 
  as 
  seen 
  from 
  below, 
  to 
  display 
  the 
  rounded 
  or 
  lobe-like 
  

   fluke 
  folds. 
  

  

  Fig. 
  5. 
  Male 
  foetus 
  of 
  Phoccena 
  communis, 
  natural 
  size 
  (N. 
  M. 
  Coll. 
  14294, 
  Province- 
  

   town, 
  Mass., 
  Freeman 
  & 
  Hillman), 
  showing 
  follicles 
  for 
  seven 
  vibrissas 
  on 
  the 
  side 
  of 
  

   the 
  snout 
  above 
  the 
  mouth. 
  

  

  Fig. 
  6. 
  View 
  from 
  below 
  of 
  the 
  perineal 
  region 
  of 
  the 
  preceding. 
  

  

  Fig. 
  7. 
  View 
  from 
  above 
  of 
  the 
  tail 
  of 
  the 
  same. 
  

  

  Fig. 
  8. 
  Side 
  view 
  of 
  a 
  somewhat 
  damaged 
  foetus 
  of 
  Phoccena 
  (N. 
  M. 
  Coll. 
  11204, 
  

   Eastport, 
  Me., 
  G. 
  B. 
  Goode.) 
  

  

  Fig. 
  9. 
  Side 
  view 
  of 
  a 
  female 
  foetus 
  of 
  Globioceplwlus 
  the 
  Caaing 
  whale 
  or 
  black- 
  

   fish, 
  natural 
  size 
  (N. 
  M. 
  Coll. 
  14295, 
  Wood's 
  Holl, 
  Mass., 
  V. 
  N. 
  Edwards). 
  

  

  Fig. 
  10. 
  View 
  of 
  the 
  tail 
  of 
  the 
  same, 
  showing 
  the 
  very 
  low 
  horizontal 
  fluke 
  folds 
  

   just 
  beginning 
  to 
  be 
  apparent 
  on 
  the 
  sides 
  of 
  the 
  end 
  of 
  the 
  tail. 
  

  

  EXPLANATION 
  OF 
  PLATE 
  II. 
  

  

  Fig. 
  11. 
  Foatus 
  of 
  the 
  narwhal, 
  natural 
  size, 
  from 
  the 
  side. 
  After 
  Eschricht. 
  

  

  Fig. 
  12. 
  Male 
  foetus 
  of 
  the 
  white 
  whale, 
  Delphinapterm, 
  from 
  the 
  side. 
  After 
  Esch- 
  

   richt. 
  

  

  Fig. 
  13. 
  Male 
  foetus 
  of 
  Delphinapterus 
  as 
  seen 
  somewhat 
  obliquely 
  from 
  below, 
  

   natural 
  size. 
  After 
  Eschricht. 
  

  

  Fig. 
  13a. 
  Tail 
  of 
  the 
  preceding, 
  showing 
  the 
  first 
  stages 
  of 
  the 
  outgrowth 
  of 
  the 
  

   fluke 
  folds. 
  After 
  Eschricht. 
  

  

  Fig. 
  14. 
  Foetal 
  kitten, 
  twice 
  natural 
  size, 
  to 
  show 
  the 
  relatively 
  early 
  differentia- 
  

   tion 
  of 
  digits 
  and 
  the 
  outwardly 
  apparent 
  wrist, 
  elbow, 
  ankle, 
  and 
  knee 
  joints, 
  and 
  

   the 
  similarity 
  in 
  curvature 
  of 
  the 
  cetacean 
  aud 
  fissiped 
  embryo 
  of 
  relatively 
  the 
  same 
  

   age. 
  From 
  a 
  specimen 
  given 
  me 
  by 
  Mr. 
  J. 
  L. 
  Wortman, 
  

  

  