MR.  R.  OWEN  ON  THE  ANATOMY  OF  THE  CHEETAH. 
133 
respect  to  the  brain  of  the  Cheetah,  I  am  disposed  to  offer  my  remarks  somewhat  more 
in  detail. 
A  remarkable  uniformity  in  the  structure  of  this  organ  prevails  throughout  the 
genus  Felis,  so  far  as  I  have  yet  had  the  opportunity  of  observing  it ;  and  this  uniformity 
obtains  not  only  in  the  general  form  of  the  cerebral  hemispheres  and  of  the  cerebellum, 
and  in  the  relative  proportions  of  these  parts  to  the  bigeminal  bodies  and  medulla  ob- 
longata, but  in  the  number  and  disposition  of  the  convolutions  of  the  cerebrum.  The 
brains  which  I  have  compared  for  this  purpose,  are  those  of  the  Lion,  Tiger,  Puma, 
Cheetah,  and  several  of  the  domestic  Cat. 
The  hemispheres  of  the  brain  cover  about  the  anterior  half  of  the  cerebellum,  having 
an  osseous  tentorium  intervening :  the  mass  of  cerebrum  posterior  to  the  corpus  callosum 
exceeds  that  which  is  anterior  to  the  same  by  about  one  fifteenth  part  of  the  longi- 
tudinal diameter  of  the  cerebrum.  The  superior  vermiform  process  occupies  a  little 
more  than  one  third  of  the  transverse  diameter  of  the  cerebellum.  Of  the  bigeminal 
bodies  the  posterior  pair  is  the  largest,  while,  as  Tiedemann  has  observed,  the  contrary  is 
the  case  in  the  Rodentia,  Ruminantia,  and  Solipeda.  The  corpora  candicantia  are  blended 
into  a  single  mass,  as  in  most  of  the  Mammalia  inferior  to  Man.  The  transverse  tract 
posterior  to  the  tuber  annulare,  and  bisected  by  the  corpora  pyramidalia,  from  which  the 
seventh  and  auditory  nerves  arise,  called  corpus  trapezoideum,  is  of  remarkable  size  in  all 
the  species  of  the  genus  Felis  above  mentioned.  The  outer  root  of  the  olfactory  nerve 
is  of  great  size,  and  emerges  from  a  remarkably  prominent  natiform  protuberance. 
After  premising  these  leading  characters  in  the  feline  brain,  I  shall  proceed  to  de- 
scribe in  detail  the  disposition  of  the  superimposed  cerebral  matter  of  the  hemispheres  : 
and  as  this  is  extended  from  before  backwards  in  the  process  of  growth,  I  shall  begin 
with  the  fissures  on  the  anterior  part.  In  the  common  Cat  the  principal  fissures,  or 
anfractuosities,  are  less  obscured  by  fissures  of  the  second  degree,  and  by  vascular 
grooves,  than  in  the  higher  Feles. 
The  first  or  most  anterior  anfractuosity  on  the  superior  surface  of  the  brain  is  lon- 
gitudinal, and  being  the  continuation  and  termination  of  the  principal  one  on  the  in- 
ferior surface,  it  extends  a  very  short  distance  from  before  backwards'.  The  next  an- 
fractuosity behind  this  is  a  transverse  one^,  extending  from  the  middle  line  about  two 
thirds  across  the  hemisphere.  At  a  short  distance  behind  this  fissure  an  anfractuosity 
commences,  which  extends  backwards  parallel  with  the  falx  cerebri,  and  which  follows 
to  a  greater  or  less  extent  the  outline  of  the  posterior  lobe  of  the  hemisphere.  The  ante- 
rior end  of  this  anfractuosity^  is  crossed  by  an  oblique  fissure,  which  varies  in  extent. 
Parallel  to  the  mesial  longitudinal  anfractuosity,  and  at  the  same  distance  from  it  as 
the  latter  is  from  the  falx,  a  second  longitudinal  anfractuosity''^  is  seen,  which  does  not 
extend  so  far  forwards  or  backwards,  but  bends  outwards  and  downwards  at  both  ex- 
tremities.   The  mass  of  cerebrum  external  to  the  second  longitudinal  anfractuosity  is 
'  8.  Figg.  1— 5,  Plate  XX.       ^  i.  Figg.  1— 6.        ^  2.  Figg.  1.  2,  4.  &  5.        ^  3.  pigg.  1.  2.  4.  &  5. 
T  2 
