Those  naturalists,  on  the  other  hand,  who  admit  the
principle   of   evolution,  and  this  is  now  admitted  by  the

***  Origin  of  Species,"  5th  edit.  p.  68.
THE  RACES  OF  MAN.  201

majority  of  rising  men,  will  feel  no  doubt  that  all  the  races
of  man  are  descended  from  a  single  primitive  stock  ;
whether  or  not  they  may  think  fit  to  designate  the  races  as
distinct  species,  for  the  sake  of  expressing  their  amount  of
difference.*  With  our  domestic  animals  the  question
whether  the  various  races  have  arisen  from  one  or  more
species  is  somewhat  different.  Although  it  may  be  admit-
ted that  all  the  races,  as  well  as  all  the  natural  species
within  the  same  genus,  have  sprung  from  the  same  primi-
tive stock,  yet  it  is  a  fit  subject  for  discussion,  whether  all
the  domestic  races  of  the  dog,  for  instance,  have  acquired
their  present  amount  of  difference  since  some  one  species
was  first  domesticated  by  man;  or  whether  they  owe  some
of  their  characters  to  inheritance  from  distinct  species,
which  had  already  been  differentiated  in  a  state  of  nature.
With  man  no  such  question  can  arise,  for  he  cannot  be  said
to  have  been  domesticated  at  any  particular  period.
