﻿142 
  W. 
  A. 
  LAMBORN. 
  

  

  and 
  dry 
  by 
  evaporation. 
  These 
  17 
  ova 
  were 
  restored 
  forthwith 
  to 
  water 
  at 
  11 
  a.m. 
  ; 
  

   on 
  examination 
  at 
  11.40 
  on 
  the 
  same 
  day 
  2 
  more 
  larvae 
  were 
  found 
  to 
  have 
  hatched. 
  

   No 
  further 
  hatchings 
  were 
  noted 
  until 
  7th 
  June, 
  when, 
  at 
  8 
  a.m., 
  another 
  newly 
  

   hatched 
  larva 
  was 
  found, 
  this 
  being 
  seven 
  days 
  after 
  the 
  eggs 
  had 
  been 
  laid, 
  five 
  days 
  

   after 
  the 
  first 
  larvae 
  had 
  hatched, 
  and 
  three 
  days 
  after 
  the 
  two 
  previous 
  larvae 
  had 
  

   emerged. 
  A 
  day 
  later, 
  8th 
  June, 
  at 
  8 
  a.m., 
  still 
  another 
  newly 
  hatched 
  larva 
  was 
  

   found. 
  

  

  In 
  the 
  case 
  of 
  another 
  A. 
  vagus, 
  138 
  ova 
  were 
  laid 
  during 
  the 
  night 
  of 
  21st 
  June 
  ; 
  

   100 
  were 
  removed 
  for 
  the 
  purposes 
  of 
  another 
  experiment 
  and 
  38 
  were 
  studied 
  in 
  

   regard 
  to 
  their 
  hatching. 
  By 
  8 
  a.m. 
  on 
  23rd 
  June, 
  15 
  larvae 
  had 
  hatched 
  ; 
  by 
  8 
  a.m. 
  

   on 
  the 
  next 
  day 
  3 
  more 
  came 
  out, 
  and 
  during 
  the 
  sixth 
  night 
  2 
  more. 
  There 
  had 
  

   been 
  no 
  change 
  in 
  conditions, 
  and 
  measures 
  had 
  been 
  taken 
  throughout 
  to 
  ensure 
  

   that 
  all 
  the 
  ova 
  were 
  floating. 
  

  

  Again, 
  in 
  the 
  case 
  of 
  another 
  A. 
  vagus, 
  130 
  eggs 
  were 
  laid 
  during 
  the 
  night 
  of 
  

   7th 
  June 
  ; 
  35 
  were 
  left 
  as 
  they 
  were, 
  the 
  remainder 
  being 
  removed 
  for 
  the 
  purposes 
  

   of 
  another 
  experiment. 
  No 
  hatching 
  took 
  place 
  until 
  10th 
  June, 
  when 
  between 
  

   8 
  a.m. 
  and 
  2 
  p.m. 
  7 
  larvae 
  emerged 
  ; 
  10 
  more 
  larvae 
  hatched 
  out 
  at 
  intervals 
  up 
  till 
  

   17th 
  June, 
  no 
  less 
  than 
  ten 
  days 
  after 
  they 
  had 
  been 
  laid. 
  

  

  In 
  the 
  case 
  of 
  A 
  . 
  karwari, 
  54 
  eggs 
  laid 
  by 
  a 
  captive 
  female 
  were 
  found 
  during 
  the 
  

   morning 
  of 
  5th 
  June. 
  By 
  the 
  8th 
  of 
  June 
  larvae 
  had 
  emerged 
  from 
  the 
  majority, 
  

   but 
  among 
  14 
  eggs 
  then 
  examined 
  5 
  were 
  found 
  with 
  their 
  shells 
  still 
  unbroken. 
  

   These 
  were 
  then 
  transferred 
  to 
  another 
  bowl, 
  and 
  on 
  11th 
  June 
  a 
  single 
  larva 
  hatched 
  

   out 
  at 
  least 
  72 
  hours 
  after 
  the 
  rest. 
  

  

  These 
  phenomena 
  of 
  the 
  hatching 
  of 
  Anophelines 
  were 
  found 
  to 
  be 
  parallelled 
  in 
  

   Stegomyia 
  albopicta. 
  For 
  example, 
  a 
  female 
  laid 
  on 
  12th 
  May 
  32 
  ova, 
  the 
  bulk 
  of 
  

   which 
  hatched 
  out 
  24 
  hours 
  later 
  ; 
  six 
  days 
  later, 
  on 
  19th 
  May, 
  6 
  more 
  larvae 
  hatched 
  

   out. 
  Again, 
  out 
  of 
  10 
  ova 
  of 
  this 
  Stegomyia 
  laid 
  on 
  17th 
  August, 
  2 
  hatched 
  within 
  

   48 
  hours, 
  and 
  3 
  more 
  at 
  intervals 
  of 
  five, 
  ten, 
  and 
  eleven 
  days 
  respectively. 
  

  

  Yet, 
  on 
  the 
  other 
  hand, 
  in 
  some 
  batches 
  of 
  ova 
  hatching 
  may 
  be 
  practically 
  

   simultaneous, 
  even 
  though 
  the 
  conditions 
  may 
  not 
  be 
  uniform 
  for 
  all 
  the 
  eggs 
  of 
  the 
  

   batch. 
  Thus, 
  on 
  the 
  24th 
  June, 
  of 
  110 
  ova 
  laid 
  by 
  an 
  A. 
  vagus 
  in 
  the 
  course 
  of 
  the 
  

   previous 
  night, 
  22 
  were 
  transferred 
  to 
  water 
  from 
  a 
  running 
  brook 
  in 
  which 
  the 
  larvae 
  

   of 
  A. 
  maculatus 
  were 
  commonly 
  obtainable; 
  28 
  to 
  an 
  old 
  infusion 
  of 
  hay; 
  13 
  to 
  

   water 
  containing 
  much 
  organic 
  matter, 
  from 
  a 
  fish-pond 
  ; 
  26 
  to 
  water 
  from 
  a 
  small 
  

   muddy 
  pool 
  ; 
  and 
  21 
  to 
  tap 
  water. 
  At 
  10 
  p.m. 
  on 
  25th 
  June 
  no 
  hatching 
  had 
  taken 
  

   place, 
  but 
  on 
  examination 
  at 
  8 
  a.m. 
  next 
  morning 
  the 
  whole 
  110 
  were 
  found 
  to 
  have 
  

   emerged. 
  

  

  Though 
  the 
  nature 
  of 
  the 
  inhibiting 
  influence 
  is 
  obscure, 
  it 
  is 
  plain 
  from 
  the 
  following 
  

   observation 
  that 
  hatching 
  may 
  be 
  delayed 
  even 
  though 
  development 
  within 
  the 
  egg 
  is 
  

   complete. 
  On 
  9th 
  August 
  20 
  ova 
  of 
  A. 
  vagus, 
  kept 
  for 
  about 
  54 
  hours 
  after 
  ovi- 
  

   position 
  in 
  a 
  moist 
  Petri 
  dish, 
  were 
  transferred 
  to 
  water. 
  Fifteen 
  hatched 
  at 
  once 
  ; 
  

   the 
  remaining 
  5, 
  unhatched 
  and 
  floating 
  on 
  the 
  water, 
  were 
  placed 
  24 
  hours 
  later 
  on 
  

   a 
  slide 
  for 
  microscopic 
  examination 
  ; 
  in 
  the 
  course 
  of 
  this 
  all 
  5 
  larvae 
  were 
  seen 
  to 
  

   wriggle 
  out, 
  possibly 
  under 
  the 
  stimulus 
  of 
  a 
  hot 
  breeze. 
  

  

  A 
  batch 
  of 
  114 
  larvae 
  of 
  A. 
  vagus, 
  found 
  in 
  a 
  breeding-bowl 
  on 
  29th 
  November, 
  

   were 
  on 
  30th 
  transferred 
  to 
  another 
  vessel. 
  Hatching 
  of 
  the 
  majority 
  immediately 
  

   occurred. 
  

  

  A 
  rather 
  interesting 
  small 
  observation 
  was 
  that 
  ova 
  kept 
  in 
  a 
  moist 
  atmosphere 
  

   in 
  a 
  closed 
  Petri 
  dish 
  often 
  did 
  not 
  hatch, 
  even 
  for 
  days, 
  until 
  the 
  lid 
  was 
  removed, 
  

   the 
  larvae 
  then 
  all 
  popping 
  out 
  within 
  a 
  minute 
  or 
  two, 
  possibly 
  by 
  reason 
  of 
  the 
  

   effect 
  of 
  change 
  of 
  air 
  on 
  their 
  enclosed 
  space, 
  or 
  of 
  the 
  effect 
  on 
  the 
  egg-shell 
  of 
  a 
  

   sudden 
  change 
  of 
  temperature. 
  The 
  occurrence 
  formed 
  a 
  convenient 
  means 
  of 
  

   enabling 
  one 
  to 
  watch 
  at 
  will 
  the 
  emergence 
  of 
  the 
  larvae. 
  These 
  came 
  out 
  with 
  their 
  

  

  