642  Martynia  and  its  Humble  Servants.        { A%J™ri884arm' 
always  meet,  to  cast  their  pollen,  in  adjacent  pairs.  The  pistil  is  also 
recurved,  and  exserted  at  all  times  beyond  the  stamens;  stigma  bifid,  the 
uppei  portion  rolled  back,  and  the  lower  rolled  inwards  and  somewhat 
longer  than  the  upper. 
On  account  of  this  arrangement,  the  anthers  overcapped  or  covered  by 
the  stigma,  it  scarcely  receives  any  pollen  by  the  natural  source,  but  most, 
if  not  all,  through  the  agency  of  insects,  in  various  ways. 
One  of  the  largest  of  its  humble  servants  in  this  cause  is  the  female  of 
Bombus  virginieus,  which  can  be  seen  in  early  mornings  flying  from 
flower  to  flower  seeking  the  nectariferous  secretion.  Its  size  will  just  admit 
its  entrance  into  the  tube  of  the  corolla,  and  it  must  consequently  brush  its 
hirsute  thorax  against  the  opened  anthers,  and  a  quantity  of  the  pollen 
adhering  to  it  by  contact  is  brushed  off  on  the  lower  lobe  of  the  stigma  of 
the  next  flower  visited ;  the  stigma  of  the  same  flower  is  not  fertilized  by 
its  own  pollen  by  this  bee,  because  of  its  sensitiveness;  when  the  insect 
brushes  against  it  on  entering,  it  immediately  closes  in  order  to  retain  any 
pollen  accumulated,  and  remains  so  for  a  lapse  of  time,  or  until  the  insect 
has  left  the  flower. 
This  bee  is  one  of  its  best  benefactors,  as  on  account  of  its  size  it  cannot 
enter  the  tube  of  the  corolla  without  touching  either  the  stigma  or  stamens 
and  deposit  pollen  obtained  from  the  last  visited  flower  and  receive  a  new 
supply  from  the  present  one;  and,  aiding  fertilization  as  described,  its  pre- 
sence is  an  assurance  of  the  complete  fertilization. 
Although  this  depends  principally  upon  the  bulk  of  the  insect,  yet  a 
number  of  these  winged  friends  are  small  and  have  each  their  peculiar 
mode  of  assistance. 
"  Nature  abhors  perpetual  self-fertilization,"  is  true,  but  she  always  sup- 
plies the  deficiency  by  having  the  aid  of  the  wind,  birds  or  insects  in  the 
distribution  of  the  pollen  ;  the  wind  for  dioecious  plants  generally,  and  for 
small  flowers  with  an  interruption  or  transposition  of  parts.  Those  depen- 
dent on  insects  have  some  special  attraction  or  solicitation  for  them,  gene- 
rally in  a  peculiar  form  of  the  flower  or  beautifully  bright  coloring  of  the 
whole  or  a  part  of  it. 
This  plant  depends  on  this  last  entirely ;  from  its  dependent  position 
and  quiet  coloring  of  the  exterior  surface  of  the  corolla  and  calyx,  and  a 
great  portion  of  the  interior  of  the  corolla,  it  would  be  passed  unnoticed  by 
the  myriads  of  winged  insects  constantly  passing  near,  were  it  not  for  the 
beautiful  marking  on  the  lower  portion  of  the  corolla.  It  begins  at  the 
insertion  of  the  corolla  on  the  receptacle,  is  prolonged  through  the  tube  in 
brilliant  golden  lines  about  the  size  of  the  filaments,  and  terminates  on  the 
lower  lobe  in  bright  golden  splotches,  in  exact  imitation  of  the  stamens 
discharging  their  pollen.  The  quiet  pearl  hue  of  the  background  adds  so 
greatly  to  the  deception  that  even  the  instructed  are  too  apt  to  consider 
them  the  essential  organs  without  further  investigation. 
One  of  its  numerous  small  friends  is  the  Mellisodes  prunosa,  very  fre- 
quent at  all  hours  of  the  day  and  extremely  busy ;  its  size  and  general 
appearance  is  similar  to  that  of  the  worker  of  Apis  mellifica,  and  unobserv- 
ant individuals  are  likely  to  confound  them  ;  but  they  can  easily  be  distin- 
guished by  the  little  triangular  white  spot  on  the  head,  just  above  the 
