Our  Canaries 
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an  aperture  destined  to  receive  the  ovule  of  largest  size  that  was  approaching 
maturity.  The  smaller  ovules  were  white  in  colour,  but  as  they  increased 
in  size  the  colour  became  more  of  a  yellow  tint.  The  three  large  ones  as 
they  developed  became  correspondingly  deeper  in  colour  till  the  largest  of 
them  was  of  the  same  tint  as  the  yolk  of  the  egg  near  the  vent. 
THE    GENESIS    OF    THE  EGG. 
"Each  of  these  three  large  ovules  was  enveloped  in  a  membrane  con- 
tinuous with  the  substance  of  the  ovary  carrying  a  network  of  blood  vessels, 
and  as  the  size  of  ovules  increased  the  membrane  became  increasingly  thin 
towards  the  free  pole  of  the  ovule,  and  it  was  suggestive  that  when  fully 
developed  the  membrane  would  give  way  at  the  thinnest  spot  and  the  ovule 
escape  free  to  be  embraced  by  that  portion  of  the  enveloping  oviduct  which 
contained  the  aperture  to  allow  of  its  ingress  into  the  lumen  of  the  duct. 
Once  inside  it  is  given  its  successive  coverings  till  it  reaches  the  vent 
complete  and  ready  for  expulsion. 
"  It  was  possible  to  estimate  the  clutch  that  would  have  been  laid ;  three 
large  developing  ovules,  one  egg  in  the  oviduct,  and  one  dropped  previously, 
making  a  total  of  five  in  all.  Assuming  an  egg  laid  every  twenty-four 
hours,  it  follows  that  counting  from  the  death  of  the  bird  the  three  largest 
ovules  would  be  capable  of  development  into  complete  eggs,  and  expelled  in 
thirty-two,  fifty-six,  and  eighty  hours  respectively. 
"The  ovary  and  reproductive  systems  are  very  vascular  and  are  con- 
nected by  nerves  with  the  brain  like  all  other  internal  organs,  and  impulses 
are  sent  from  them  to  the  brain,  and  the  resulting  ones  from  the  brain  are 
capable  of  influencing  the  blood  supply  and  the  activity  of  the  ovary." 
EXCITING  CAUSES. 
"  Given,  therefore,  ovules  in  such  a  state  that  they  are  capable  of  coming 
to  maturity,  egg  production  can  be  precipitated  by : — -(i.)  The  seasonable 
impulse :  from  the  inherited  instinct  to  reproduce.  This  takes  place  in  the 
early  part  of  the  year  with  the  advent  of  (ii.)  Warm  weather :  which  not 
only  improves  the  general  health  of  the  hen  and  increases  the  circulation 
of  the  blood,  but  also  by  its  presence  gives  promise  of  greater  ease  in 
obtaining  the  (iii.)  Increased  food  supply  :  necessary  for  egg  production  and 
the  feeding  of  the  prospective  young,  (iv.)  A  stimulus  to  reproduction  by 
the  singing  and  proximity  of  the  cock.  In  response  to  such  stimulation, 
impulses  are  sent  out  to  the  ovaries  and  reproductive  organs,  inducing  a 
greater  flow  of  blood  to  them.  This  determines  a  greater  supply  of  nourish- 
ment locally,  which  is  conducive  to  growth  and  development.  The  proximity 
of  the  cock  is  not  in  itself  an  essential  for  egg  production,  as  hens  will  lay 
