﻿PKOCEEDTNGS 
  OF 
  THE 
  FOURTH 
  ENTOMOLOGICAL 
  MEETING 
  203 
  

  

  ing, 
  includes 
  some 
  of 
  the 
  chemicals 
  in 
  which 
  the 
  least 
  number 
  of 
  eggs 
  were 
  

   laid.* 
  They 
  are 
  : 
  — 
  

  

  Acids 
  : 
  Citric, 
  Oxalic, 
  Malic, 
  Lactic, 
  Sulphuric 
  and 
  Hydrochloric. 
  

  

  Alkalies 
  : 
  Caustic 
  potash 
  and 
  Caustic 
  soda. 
  The 
  substance 
  in 
  which 
  

   the 
  larva3 
  and 
  pupae 
  developed 
  most 
  quickly 
  is 
  also 
  the 
  same 
  in 
  which 
  

   the 
  largest 
  number 
  of 
  eggs 
  were 
  laid, 
  i.e., 
  Sodium 
  tartrate. 
  

  

  One 
  remarkable 
  fact 
  about 
  Sodium 
  tartrate 
  is 
  that 
  the 
  larvse 
  developed 
  

   very 
  fairly 
  in 
  the 
  beginning 
  of 
  the 
  experiment 
  and 
  nearly 
  achieved 
  

   maturity, 
  one 
  week 
  after 
  their 
  hatching. 
  But 
  after 
  that 
  their 
  progress 
  

   was 
  at 
  a 
  stand-still 
  for 
  about 
  10 
  days 
  and 
  they 
  did 
  not 
  pupate 
  until 
  

   some 
  food 
  in 
  the 
  form 
  of 
  sanatogen 
  (as 
  referred 
  to 
  in 
  the 
  beginning) 
  

   was 
  added. 
  Another 
  striking 
  fact 
  is 
  that 
  it 
  was 
  also 
  in 
  the 
  first 
  week 
  of 
  

   their 
  larval 
  stage, 
  that 
  the 
  number 
  came 
  down 
  from 
  98 
  to 
  7 
  only, 
  all 
  

   of 
  which 
  pupated 
  afterwards. 
  Of 
  course 
  the 
  mortality 
  was 
  high 
  in 
  

   the 
  beginning 
  of 
  the 
  larval 
  stage 
  in 
  all 
  these 
  solutions, 
  but 
  not 
  to 
  such 
  

   an 
  extent. 
  

  

  So 
  far 
  as 
  I 
  have 
  tried, 
  Sodium 
  tartrate 
  seemed 
  to 
  be 
  very 
  well 
  adapted 
  

   to 
  hastening 
  the 
  development 
  of 
  mosquito 
  larvae. 
  

  

  Results 
  obtained 
  with 
  Sodium 
  chloride 
  : 
  — 
  

  

  Per 
  cent. 
  Result. 
  

  

  2-0 
  . 
  . 
  . 
  . 
  Larvse 
  hatched 
  and 
  died 
  immediately. 
  

  

  1-0 
  . 
  . 
  . 
  . 
  Larvse 
  hatched 
  and 
  died 
  within 
  24 
  hours. 
  

  

  0-7'4 
  . 
  . 
  . 
  Larvse 
  hatched 
  but 
  out 
  of 
  57 
  only 
  2 
  were 
  alive 
  on 
  tlie 
  

  

  18th 
  day 
  ; 
  1 
  more 
  died 
  on 
  the 
  23rd 
  day 
  and 
  the 
  

   remaining 
  one 
  pupated 
  and 
  died 
  on 
  the 
  25th 
  day. 
  

  

  0-6 
  . 
  . 
  . 
  Life 
  cycle 
  complete. 
  

  

  0-58 
  . 
  . 
  . 
  Ditto. 
  

  

  0-5 
  ... 
  Ditto. 
  

  

  0-29 
  . 
  . 
  Ditto. 
  

  

  0-25 
  . 
  . 
  Ditto. 
  

  

  Results 
  obtained 
  with 
  Potassium 
  chloride 
  : 
  — 
  

  

  Per 
  cent. 
  Results. 
  

  

  0-74 
  . 
  . 
  . 
  Larvse 
  hatched 
  but 
  died 
  within 
  8 
  days. 
  

  

  0-58 
  . 
  ' 
  .' 
  . 
  Larvse 
  hatched 
  but 
  died 
  within 
  9 
  days. 
  

  

  0-29 
  . 
  . 
  . 
  Larva; 
  hatched, 
  pupated 
  and 
  mosquitos 
  emerged. 
  

  

  * 
  Vide 
  " 
  Oviposition 
  in 
  Culicidse 
  " 
  by 
  Mr. 
  S. 
  K. 
  Sen 
  and 
  H. 
  N. 
  Sharmo 
  presented 
  

   with 
  this 
  paper 
  to 
  the 
  Meeting. 
  

  

  