J  ^5  Our  Canaries 
"  {it.)  Alteration  from  the  normal  shape. — The  egg  is  laid  with  the  thicker 
end  first,  and  the  natural  egg  shape  is  the  one  which  presents  the  greatest 
facilities  for  expulsion.  Compare  the  two  figures  of  the  real  egg-shaped  one 
and  the  more  rounded  one. 
The  greatest  circumference  A  C  has  to  pass  through  the  resistance  of  the 
opening   of  oviduct   into    the    cloaca    and    the   vent,    and    these    two  are 
approximated   close   together  at   the   time   of  laying.     Once  past  this  line 
ABC  the  elastic  recoil  of  the  stretched  parts '  running  over  a  diminishing 
cone  surface  to  D  shoots  the  egg  out.     In  the  usual-shaped  egg  {fig.  i)  the 
distance  B  E  is  greater  than  in  fig.  2,  the  more  rounded  egg.    This  means 
that  the  diameter  of  the  cone  increases    more   gradually  from   E  to  B  m 
fig.  I  than  in  fig.  2,  and  the  point  is  finer.     The   blunt  end  oi  fig.  2  is 
less  easily  inserted  into 
the  resistance  of  the  end 
of    oviduct,    and  more 
force  is  required  to  dilate 
the   latter.      The  finer 
point  and  more  gradually 
increased  diameter  of  the 
cone   form  a  much  better  dilating  wedge  than  the  blunt  pomt  with  a  more 
rapidly  increased  diameter.    It  is  therefore  obvious  that  the  more  pointed  and 
elongated  the  egg  is  from  the  end  to  the  greatest  diameter  the  more  easily  the 
resistance  of  the  parts  in  front  will  be  overcome,  and  that  a  blunt  point  and  more 
rounded  egg  with  a  shorter  distance  from  the  presenting  end  to  the  greatest 
diameter  are  structural  disadvantages  to  easy  expulsion. 
"  (m  )  Large  Size  of  the  Egg.-I^^e  larger  the  egg  the  greater  the  distension  of 
the  soft  parts  necessary  before  it  can  be  laid.  The  logical  deductions  from  the 
study  of  these  factors  in  egg-binding  is  that  treatment  should  be  preventive,  and 
failing  that  it  should  be  active.  Avoid  constipation  by  sufficient  green  food,  and 
salts  if  necessary.  Avoid  over-fatness  by  regulation  of  diet  and  oily  seeds  Do 
not  breed  with  old  hens,  or  those  who  show  any  weakness  in  general  health,  or 
over-work  during  the  preceding  show  season.  Do  not  take  too  many  nests  m  the 
season  from  a  hen.  The  giving  of  niger  seed  is  said  to  have  a  beneficial  effect  m 
the  prevention  of  egg-binding,  but  my  own  birds  never  have  it,  and  I  have  every 
reason  to  believe  they  are  as  free  from  egg-bindmg  as  possible,  as  I  have  never  had 
an  egg-bound  Canary.  Plenty  of  crushed  mortar  is,  I  believe,  essential,  and  judgmg 
by  the  pounds  of  it  mine  consume  it  is  quite  harmless  both  to  the  old  birds  and 
nestlings.  1  •  ,  t 
"  Assuming  that  egg-binding  should  occur,  and  that  the  egg  which  I  was  cer- 
tain from  the  size,  shape  and  appearance  of  the  hen,  say,  in  the  evening  was  due  to 
appear  next  morning  and  it  did  not,  I  should  judge  from  the  condition  of  the  hen 
whether  she  was  in  difficulties.    She  might  be  humped  up,  feathers  puffed  out  and 
