﻿OF 
  THE 
  SOUTHERN 
  PROVINCES, 
  NIGERIA. 
  211 
  

  

  as 
  the 
  day 
  advanced 
  to 
  wait 
  till 
  night-fall 
  before 
  resuming 
  their 
  activities, 
  eventually 
  

   dying 
  in 
  such 
  numbers 
  that 
  handfuls 
  could 
  be 
  gathered 
  on 
  each 
  sill. 
  

  

  With 
  a 
  view 
  to 
  estimating 
  the 
  relative 
  increase 
  of, 
  and 
  the 
  damage 
  done 
  by, 
  Calandra 
  

   and 
  Tribolium 
  respectively, 
  the 
  following 
  experiments 
  were 
  conducted. 
  On 
  27th 
  

   October, 
  half 
  a 
  pound 
  of 
  thoroughly 
  sun-dried 
  new 
  maize 
  was 
  placed 
  in 
  a 
  well 
  closed 
  

   glass 
  jar 
  with 
  fifty 
  Calandra. 
  When 
  examined 
  again 
  on 
  30th 
  December, 
  the 
  maize, 
  

   shaken 
  free 
  of 
  debris 
  produced 
  by 
  the 
  attack, 
  was 
  found 
  to 
  have 
  lost 
  1 
  J 
  oz. 
  in 
  weight, 
  

   and 
  though 
  only 
  40 
  per 
  cent, 
  of 
  the 
  seeds 
  had 
  been 
  attacked, 
  420 
  weevils 
  and 
  a 
  large 
  

   number 
  of 
  larvae 
  were 
  found. 
  

  

  On 
  the 
  same 
  day 
  half 
  a 
  pound 
  of 
  maize 
  was 
  placed 
  in 
  a 
  sealed 
  jar 
  with 
  50 
  Tribolium. 
  

   On 
  30th 
  December 
  the 
  grain, 
  shaken 
  free 
  of 
  debris, 
  had 
  lost 
  2 
  oz. 
  in 
  weight, 
  and 
  though 
  

   the 
  beetles, 
  exclusive 
  of 
  larvae, 
  had 
  only 
  increased 
  to 
  167, 
  the 
  grain 
  had 
  suffered 
  to 
  

   the 
  extent 
  of 
  about 
  65 
  per 
  cent., 
  a 
  much 
  greater 
  damage 
  therefore 
  than 
  in 
  the 
  first 
  

   experiment. 
  The 
  explanation 
  of 
  this 
  appears 
  to 
  be 
  that 
  Tribolium 
  bores 
  into 
  a 
  grain, 
  

   deposits 
  an 
  egg 
  or 
  feeds, 
  and 
  then 
  goes 
  on 
  to 
  another 
  grain, 
  whereas 
  Calandra 
  will 
  

   contentedly 
  feed 
  away 
  and 
  oviposit 
  in 
  a 
  single 
  grain. 
  It 
  was 
  found 
  in 
  the 
  laboratory 
  

   that 
  a 
  single 
  grain 
  of 
  maize 
  contains 
  sufficient 
  nourishment 
  to 
  support 
  a 
  female 
  

   Calandra 
  and 
  her 
  developing 
  offspring 
  for 
  five 
  weeks, 
  at 
  the 
  end 
  of 
  which 
  time 
  her 
  

   mature 
  offspring 
  may 
  number 
  five 
  or 
  six, 
  all 
  of 
  which 
  have 
  fed 
  up 
  on 
  this 
  one 
  grain. 
  

   These 
  results 
  were 
  not 
  obtained 
  in 
  the 
  case 
  of 
  Tribolium, 
  though 
  in 
  one 
  case 
  a 
  single 
  

   mature 
  insect 
  was 
  bred 
  out 
  in 
  the 
  course 
  of 
  a 
  month 
  from 
  one 
  grain, 
  which 
  also 
  sup- 
  

   ported 
  the 
  female 
  parent 
  during 
  this 
  time. 
  

  

  Further 
  experiments 
  show 
  that, 
  though 
  both 
  Calandra 
  and 
  Tribolium 
  are 
  found 
  

   in 
  cobs 
  in 
  the 
  field, 
  yet 
  Calandra 
  does 
  not 
  seem 
  to 
  have 
  the 
  power, 
  possessed 
  by 
  

   Tribolium, 
  of 
  boring 
  through 
  the 
  unbroken 
  sheath 
  of 
  the 
  cob. 
  Calandra 
  placed 
  on 
  

   such 
  a 
  sheath 
  in 
  glass 
  tubes, 
  mouth 
  downwards, 
  died 
  a 
  lingering 
  death 
  after 
  ten 
  to 
  

   fifteen 
  days 
  without 
  having 
  pierced 
  it, 
  whereas 
  Tribolium 
  very 
  soon 
  disappeared 
  

   into 
  the 
  cob. 
  In 
  all 
  probability, 
  therefore, 
  Calandra 
  obtains 
  access 
  to 
  the 
  cob 
  through 
  

   the 
  opening 
  at 
  the 
  apex 
  from 
  which 
  the 
  silk 
  has 
  dropped 
  out, 
  or 
  through 
  holes 
  made 
  

   in 
  the 
  sheath 
  by 
  borers. 
  

  

  A 
  few 
  experiments 
  were 
  made 
  in 
  the 
  hope 
  of 
  finding 
  if 
  possible 
  a 
  sacking 
  material 
  

   proof 
  against 
  Calandra 
  and 
  Tribolium 
  for 
  the 
  storage 
  of 
  fumigated 
  maize, 
  but 
  the 
  

   only 
  fact 
  established 
  was 
  that 
  the 
  weevil 
  does 
  not 
  penetrate 
  a 
  coarse 
  drill, 
  though 
  

   unfortunately 
  Tribolium 
  has 
  no 
  difficulty 
  in 
  doing 
  so. 
  

  

  As 
  has 
  been 
  already 
  noted, 
  the 
  Pyralid 
  moth, 
  Mussidia, 
  is 
  a 
  formidable 
  pest 
  in 
  

   stored 
  maize. 
  The 
  larva 
  when 
  first 
  hatched 
  bores 
  into 
  a 
  grain 
  and 
  eats 
  out 
  the 
  soft 
  

   nitrogenous 
  radicle 
  at 
  the 
  apex, 
  leaving 
  the 
  harder 
  part 
  untouched, 
  so 
  that 
  a 
  grain 
  

   attacked 
  comes 
  to 
  resemble 
  in 
  shape 
  a 
  small 
  double 
  tooth 
  with 
  two 
  fang-like 
  processes. 
  

   When 
  this 
  is 
  finished, 
  if 
  the 
  grain 
  is 
  still 
  on 
  the 
  cob, 
  it 
  gradually 
  tunnels 
  along 
  the 
  

   whole 
  length 
  of 
  a 
  row, 
  eating 
  away 
  the 
  softer 
  portions 
  and 
  leaving 
  the 
  hard 
  shells, 
  

   and 
  it 
  pupates 
  eventually 
  in 
  a 
  silken 
  cocoon 
  in 
  this 
  tunnel. 
  There 
  is 
  often 
  no 
  surface 
  

   evidence 
  of 
  the 
  damage 
  which 
  is 
  proceeding. 
  

  

  When 
  shelled 
  maize 
  is 
  attacked 
  the 
  caterpillar 
  spins 
  grains 
  together 
  and 
  then 
  bores 
  

   through 
  the 
  mass. 
  Silk 
  web 
  with 
  characteristic 
  damage 
  is 
  to 
  be 
  looked 
  on 
  as 
  infallible 
  

   evidence 
  as 
  to 
  the 
  presence 
  of 
  this 
  moth. 
  A 
  rough 
  estimate 
  of 
  the 
  damage 
  done 
  by 
  

   the 
  pest 
  was 
  obtained 
  by 
  placing, 
  on 
  30th 
  October, 
  four 
  female 
  moths 
  in 
  a 
  jar 
  

  

  