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MR.  R.  OWEN  ON  THE  ANATOMY  OF  THE  CHEETAH. 
traversed  perpendicularly  or  transversely  by  three  principal  anfractuosities ' ,  so  that  each 
hemisphere  posterior  to  the  first  transverse  fissure  is  composed  of  two  mesial  longitudi- 
nal convolutions  with  their  deflected  extremities  (a.  &  &.),  and  four  lateral  perpendicular 
convolutions  (c.  d.  e.  &/.),  which  may  be  called  principal  or  primary  convolutions. 
In  the  Cheetah  the  first  longitudinal  convolution  a.  is  traversed  longitudinally  by  an 
interrupted  fissure^,  which,  in  the  individual  examined,  extended  further  in  the  right 
than  in  the  left  hemisphere ;  and  I  have  observed  that  these  secondary  fissures  are  in 
general  less  symmetrical  than  the  primary  ones.  In  the  Cat  there  is  no  increase  of  the 
surface  of  the  brain  by  a  secondary  fissure  of  this  kind.  In  the  Lion  there  is  a  shght 
trace  of  it  at  the  middle,  and  again  at  the  posterior  end  of  convolution  a.  In  the 
Cheetah,  Lion,  Tiger  and  Puma,  there  are  a  few  irregular  transverse  intersections-*, 
extending  about  half  way  across  this  convolution  from  both  sides. 
The  convolution  b.  in  the  Cheetah  dififers  from  that  in  the  Lion,  Tiger,  Puma,  and 
Cat,  chiefly  in  its  elevation  above  the  plane  of  the  hemisphere.  In  both  the  Cheetah 
and  Lion  it  is  broader  in  proportion  to  a.  than  in  the  Cat.  The  mass  formed  by  the 
blending  together  of  the  convolutions  a.  and  6.  posteriorly,  presents  more  partial  fissures 
in  the  Cheetah  than  in  the  Lion  or  Cat ;  the  continuation  outwards  of  the  secondary 
fissure  7  is  constant  in  all  the  Feles. 
Of  the  lateral  convolutions  the  middle  ones  d.  and  e.  are  the  smallest  in  all  the  Feles, 
and  do  not  project  so  far  out  as  /.  In  the  Cat  the  diflerence  is  but  slight ;  in  the 
lAon  it  is  greater ;  and  in  the  Cheetah  the  proportionate  size  of  these  convolutions  is  a 
little  more  increased. 
The  small  convolution  g.  is  of  about  the  same  proportionate  size  in  all  the  Feles ; 
but  the  brain  at  the  part  where  b.  and  c.  meet  is  broader  in  the  Cheetah"^  than  in  either 
the  Lion  or  the  Cat.  The  cerebrum  is  also  proportionately  broader  than  the  cerebellum 
in  the  Cheetah  than  in  any  of  the  Feles  which  I  have  examined. 
At  the  base  of  the  hemispheres  the  principal  and  most  constant  anfractuosity  is  lon- 
gitudinal, extending  along  the  outside  of  the  olfactory  nerve,  and  terminating  ante- 
riorly in  8.  Fig.  1. 
Another  longitudinal  fissure,  posterior  to  the  preceding,  separates  the  natiform  pro- 
tuberance from  the  blended  convolutions  e.  and/ 
On  the  mesial  surface  of  the  hemispheres  the  anfractuosities  are  the  same  in  number 
in  the  Cat  and  Cheetah,  but  are  of  greater  extent  in  the  latter.  The  transverse  anfrac- 
tuosity^ extends  in  both  species  downwards  and  backwards,  to  opposite  the  middle  of  the 
corpus  callosum.  I  have  found  the  same  disposition  of  this  convolution  in  the  brains  of 
two  Lions ;  but  Tiedemann,  in  his  view  of  the  brain  of  the  Lion^,  does  not  represent  it 
'  4.  5.  &  6.  Figg.  2.  &  5.  2  7.  pig.  1,  3  9.  Yig.  1. 
This  difference  is  expressed  in  the  form  of  the  cranium,  which,  as  Cuvier  has  observed  (Ossemens  Foss., 
torn.  iv.  p.  44G.),  is  the  shortest,  most  convex,  and  proportionately  the  broadest,  of  any  of  the  species  of  Felis. 
'  1.  Figg.  1.  &3.  6  Icones  Cerebri  Simiarum,  &c.  Tab.  iii.  fig.  5. 
