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Our  Canaries 
is  also  possible  for  the  reproductive  organs  to  lie  dormant  for  a  considerable 
period,  as  is  evidenced  by  hens  which  show  no  indication  at  all  of  building  or 
laying  their  first  year,  but  do  so  the  second  year,  or  are  made  to  miss  a  year  by 
being  kept  alone  during  the  second  breeding  season,  and  begin  again  if  opportunity 
occurs  the  following  year." 
A  NATURAL  CYCLE. 
"  In  a  hen  that  has  reached  an  age  when  it  is  capable  of  laying  eggs,  and 
that  is  possessed  of  a  normal  reproductive  system,  there  is  an  instinct  at  a  certain 
time  of  the  year  to  accomplish  a  reproductive  cycle  for  the  propagation  of  the 
species.  The  cycle  consists  of  building  a  nest,  the  laying  of  eggs,  incubation  of 
the  latter,  hatching  and  rearing  the  young.  In  order  that  the  cycle  may  be  fully 
carried  to  a  successful  issue  the  presence  of  the  cock  is  necessary  before  the  eggs 
are  laid. 
"  That  eggs  may  be  laid  an  ovary  is  necessary  for  the  production  of  the 
internal  part  or  yolk.  An  oviduct  must  be  present  to  receive  the  yolk  and  cover 
it  with  the  white  of  the  egg,  the  membranes  and  the  shell,  and  conduct  the  egg 
from  the  ovary  to  the  vent  that  it  may  be  deposited  external  to  the  bird  for 
future  incubation.  The  organs  are  best  studied  in  a  hen  that  is  actually  engaged 
in  egg  laying.  With  this  object  in  view  the  hen  quoted  as  instance  No.  3  was  given 
late  at  night  an  overdose  of  chloroform  vapour,  the  first  egg  of  the  clutch  having  been 
dropped  in  the  early  morning  of  the  same  day.  The  next  egg  would  have  been 
due  in  the  early  hours  of  the  following  morning,  so  that  the  death  of  the  hen 
occurred  as  nearly  as  can  be  estimated  about  eight  hours  before  the  second 
egg  of  the  clutch  would  have  been  laid. 
THE  INTERNAL  ECONOMY. 
"  On  opening  up  the  body  of  this  hen,  the  egg  due  in  eight  hours  was 
found  situated  in  its  lowest  portion,  partially  covered  on  the  left  side  by  the 
convoluted  oviduct.  On  the  right  side  were  the  intestines,  and  above  the 
stomach  was  in  contact  with  the  upper  portion  of  the  egg,  which  lay  with  its 
narrower  end  towards  the  vent.  It  was  not  until  the  convolutions  of  the 
oviduct  were  turned  aside  that  the  ovary  came  into  view,  lying  high  up  behind 
the  stomach  on  the  left-hand  side  of  the  body  of  the  bird.  Though  the  ovary 
was  in  contact  with  the  upper  portion  of  the  egg,  it  was  found  that  the  oviduct 
on  being  separated  and  laid  out  straight  was  over  three  inches  long. 
"A  sketch  (shown  on  page  115)  has  been  made  showing  these  organs  as 
nearly  as  possible  actual  size  but,  for  distinctiveness,  not  in  their  anatomical 
relations.  This  shows  the  ovary  containing  60-70  countable  round  globular 
bodies,  called  ovules,  in  various  stages  of  development ;  a  convoluted  oviduct 
empty  at  upper  end,  but  containing  an  egg  close  to  the  vent.  This  egg  was 
full,  but  the  shell  was  thinner  than  usual,  indicating  that  the  process  of 
shell  formation  was  not  yet  complete.    In  the  upper  end  of  the  oviduct  was 
