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MR.  R.  OWEN  ON  THE  ANATOMY  OF  THE  CHEETAH. 
In  the  domestic  Cat,  in  Felis  planiceps,  Vig.  and  Horsf.,  and  in  Felis  Caracal,  Schreb., 
the  OS  hyoides  is  connected  to  the  cranium,  as  in  the  Genet  and  the  Dog,  by  an  unin- 
terrupted chain  of  bones  :  this  structure,  indeed,  has  afforded  Professor  Geoffroy  one  of 
his  illustrations  of  the  essential  composition  of  an  os  hyoides.  The  same  structure 
obtains  in  the  Cheetah.  From  the  difference  in  the  voice,  the  feline  animals  might  have 
been  expected,  a,  priori,  to  present  some  differences  in  that  part  of  their  anatomy  which 
relates  to  it. 
A  vertical  elliptic  pupil  (which  is  so  well  calculated  to  exclude  a  too  strong  light 
from  a  retina  adapted  to  crepuscular  vision,  and  at  the  same  time  to  admit  of  a  rapid 
and  sufficient  expansion  for  the  exercise  of  sight  in  the  gloom  of  the  evening,)  is  that 
form  which  is  met  with  in  all  the  smaller  and  weaker  species  of  the  feline  genus  :  but 
in  the  more  powerful  and  bolder  species,  which  dare  to  attack  a  larger  prey  in  the  face 
of  day,  the  pupil  is  of  a  circular  form.  The  Cheetah  agrees  in  this  respect  with  the 
Ldon,  the  Tiger,  the  Leopard,  and  the  Jaguar ;  and,  from  its  natural  docility  and  habits, 
may  be  regarded  as  the  most  strictly  diurnal  of  the  whole  genus. 
The  soft  parts  of  living  prey  forming  the  food  of  the  whole  tribe,  a  consequent  corre- 
spondence prevails  in  the  structure  of  the  digestive  organs.  The  oesophagus  is  remark- 
able for  its  width  and  its  loose  mode  of  connexion  in  the  chest,  both  of  which  facilitate 
the  passage  of  the  coarsely  divided  flesh.  The  lower  half  of  this  tube  is  characterized 
by  transverse  rug(B  ;  and  the  muscular  fibres,  which  are  at  first  disposed  spirally, — the 
two  layers  in  opposite  directions, — assume  at  this  part  a  disposition  analogous  to  that 
in  the  human  subject,  the  outer  layer  being  longitudinal,  the  inner  one  transverse. 
I  have  also  discovered  at  this  part  of  the  (esophagus  a  third  layer  of  muscular  fibres, 
which  is  longitudinal,  and  more  internal  than  the  transverse  :  this  layer  does  not  extend 
beyond  that  part  of  the  oesophagus  in  which  the  transverse  rugce  of  the  lining  membrane 
exist ;  and  as  it  adheres  closely  to  the  membrane,  I  am  inclined  to  believe  that  it  pro- 
duces the  rugous  disposition  peculiar  to  that  part :  a  preparation  demonstrating  this 
muscular  layer  in  the  Ldon,  is  in  the  Museum  of  the  College  of  Surgeons.  A  similar 
structure  exists  in  the  Cheetah. 
The  oesophagus  is  not  prolonged  into  the  abdomen  in  any  of  the  feline  tribe,  but  ter- 
minates at  once  in  the  stomach.  This  viscus,  compared  with  the  human  stomach,  pre- 
sents a  less  extent  of  the  left  blind  extremity,  or  saccus  ccecus  of  Haller ;  the  pyloric 
half  is  more  tubular,  and  is  more  abruptly  bent  upon  the  cardiac ;  the  lining  mem- 
brane presents  fewer  ruga ;  and  the  disposition  of  these,  when  the  stomach  is  con- 
tracted, is  more  regularly  in  the  longitudinal  direction.  But  the  most  marked  cha- 
racteristic of  the  feline  stomach  is  the  mode  in  which  the  lesser  omentum  is  continued 
upon  it :  this  duplicature  is  not  attached  in  a  regular  line  to  the  lesser  curvature,  but 
extends  in  a  scolloped  form  upon  the  anterior  surface,  upon  which  the  branches  of  the 
coronary  artery  are  further  continued  before  penetrating  the  muscular  coat.  The  Cheetah 
