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MR.  R.  OWEN  ON  THE  OSTEOLOGY  OF 
PLATE  XLVIII. 
Side  view  of  the  skeletons  of  the  adult  and  young  Chimpanzee  {Simla  Troglodytes, 
Blum.),  the  latter  being  of  that  age  when  the  first  permanent  molares  have  been  ac- 
quired, and  before  the  shedding  of  any  of  the  deciduous  teeth. 
PLATE  XLIX. 
Side  view  of  the  skeletons  of  the  adult  and  young  Orang  Utan  {Simia  Satyrus,  Linn.). 
The  young  skeleton  is  of  a  corresponding  age  with  that  of  the  Chimpanzee  in  the  pre- 
ceding Plate :  like  it,  it  exhibits  the  anthropoid  character  in  the  relative  smallness  of 
the  face  to  the  cranium,  resulting  from  the  state  of  dentition,  but  shows  the  corre- 
spondency with  the  adult  skeleton  in  the  number  of  ribs  and  in  the  relative  proportions 
of  the  upper  and  lower  extremities.  With  regard  to  the  number  of  vertehroe,  it  must  be 
observed,  that  the  figure  of  the  adult  skeleton,  being  taken,  by  permission  of  the  Board 
of  Curators,  from  the  specimen  in  the  Museum  of  the  Royal  College  of  Surgeons,  ex- 
hibits the  abnormal  number  of  five  lumbar  vertebra,  instead  of  four,  which  is  the  number 
existing  in  the  trunk  of  the  mature  Orang  preserved  in  the  Museum  of  the  Zoological 
Society  and  in  the  skeleton  in  the  Museum  of  Comparative  Anatomy  in  the  Jardin  des 
Plantes. 
PLATE  L. 
Front  view  of  the  skeletons  of  the  adult  Chimpanzee  and  Orang  Utan.  The  trunk  of 
the  latter  is  figured  from  the  specimen  belonging  to  the  Zoological  Society,  and  shows 
the  normal  number  of  lumbar  vertebra,  which  is  the  same  as  in  the  Chimpanzee.  The 
proportions  are  given  according  to  the  size  indicated  by  a  cranium  and  ulna  and  radius 
in  the  Museum  of  the  Royal  College  of  Surgeons  ;  from  which  it  would  appear  that  the 
height  of  the  animal,  fairly  measured  from  the  vertex  to  the  sole  of  the  foot,  could  not 
exceed  five  feet. 
PLATE  LI. 
Side  view  of  the  cranium  of  the  adult  Chimpanzee,  natural  size.  On  the  left  hand  are 
figured  the  germs  of  the  permanent  teeth,  taken  from  the  skull  of  a  young  Chimpanzee 
at  the  period  when  the  first  true  molar,  /,  has  appeared. 
a.  The  first  incisor. 
b.  The  second  incisor. 
c.  The  apex  of  the  crown  of  the  laniary  or  cuspidatus. 
