This  series  of  forms  seems  to  show  tlint  all  twelve  spe-
cies Jire  descended  from  a  form  with  phii]i  ma)es  and
plain  females  ;  that  this  character  has  been  retain^nl  in
both  sexes  by  one  species,  but  that  the  males  have  been
greatly  modified  in  the  other  eleven,  while  in  two  of
them  the  females  have  inherited,  to  an  imperfect  degree,
the  modification  of  the  males  of  their  own  species,  and
in  the  other  nine  the  females  have  remained  stationary
and  have  shown  no  tendency  to  inherit  the  modification
of  their  male  parents.
In  an  allied  genus,  Eubagis,  the  males  of  most,  of  the
species  are  decorated  with  beautiful  metallic  tints,  in  a
diversified  manner,  and  differ  much  from  the  females.
The  females  throughout  the  genus,  on  the  other  hand,
retain  a  uniform  style  of  coloring,  so  that  they  common-
ly resemble  each  other  much  more  closely  than  they  re-
semble their  own  proper  males.
Darwin  concludes  {Variation,  Vol.  I.,  p.  378)  that
'^  when  the  sexes  of  butterflies  differ,  the  male,  as  a  gen-
eral rule,  is  the  most  beautiful,  and  departs  most  from
tiie  usual  type  of  coloring  of  the  group  to  which  the  spe-
cies belongs.  Hence  in  most  groups  the  females  of  the
several  species  resemble  each  other  much  more  closely
than  do  the  males,"  .  .  .  ^' and  this  indicates  that
the  males  have  iindergone  a  greater  amount  of  modifica-
tion than  the  females P  There  are  many  striking  excep-
tions to  this  law,  which  is  general  but  not  universal.
Certain  of  the  most  remarkable  exceptions,  such  as  the
occurrence  of  ])olymorphic  female  butterflies,  and  of  the
various  female  forms  among  the  social  insects,  will  be
discussed  at  the  end  of  the  next  chapter.
