These  conditions,  air  and  warmth,  are  so  fundamental
that  no  Dung-beetle  neglects  them.     The  nutritive  hoards


30      THE  LIFE  AND  LOVE  OF  THE  INSECT

vary  in  form,  as  we  shall  have  occasion  to  perceive  :
in  addition  to  the  pear,  such  shapes  as  the  cylinder,  the
ovoid,  the  pill  and  the  thimble  are  adopted,  according  to
the  species  of  the  manipulator  ;  but,  amid  this  diversity
of  outline,  one  feature  of  the  first  importance  remains
constant,  which  is  the  egg  lodged  in  a  hatching-chamber
close  to  the  surface,  providing  an  excellent  means  for
the  easy  access  of  air  and  warmth.  And  the  most
gifted  in  this  delicate  art  is  the  Sacred  Beetle  with  her
pear,

I  was  urging  just  now  that  this  first  of  Dung-kneaders
behaved  with  a  logic  that  rivals  our  own.  At  the  point
to  which  we  have  come,  the  proof  of  my  statement  is  es-
tablished. Nay,  better  still.  Let  us  submit  the  following
problem  to  our  leading  scientific  lights  :  a  germ  is  accom-
panied by  a  mass  of  victuals  liable  soon  to  be  rendered
useless  by  desiccation.  How  should  the  alimentary  mass
be  shaped  ?  Where  should  the  egg  be  laid  so  as  to  be
easily  influenced  by  air  and  warmth  ?

The  first  question  of  the  problem  has  already  been
answered.  Knowing  that  evaporation  is  in  proportion
to  the  extent  of  the  evaporating  surface,  science  declares
that  the  victuals  shall  be  arranged  in  a  ball,  because
the  spherical  form  is  that  which  encloses  the  greatest
amount  of  material  within  the  smallest  surface.  As  for
the  egg,  since  it  requires  a  protectmg  sheath  to  avoid  any
harmful  contact,  it  shall  be  contained  within  a  thin,
cylindrical  case  ;  and  this  case  shall  be  implanted  on  the
sphere.
