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  Soap 
  is 
  an 
  important 
  contact 
  insecticide, 
  and 
  most 
  contact 
  poisons 
  

   contain 
  it 
  in 
  greater 
  or 
  lesser 
  proportions, 
  such 
  as, 
  for 
  example, 
  quassia- 
  

   soap 
  mixture, 
  Dufour's 
  worm 
  poison 
  and 
  Nessler's 
  remedy 
  for 
  Aphids. 
  

   The 
  most 
  essential 
  character 
  of 
  a 
  contact 
  poison 
  is 
  its 
  power 
  to 
  soak 
  

   into 
  the 
  hairy 
  or 
  waxlike 
  covering 
  of 
  insects. 
  This 
  power 
  depends, 
  

   according 
  to 
  Vermorel 
  and 
  Daxtony 
  (1910), 
  on 
  the 
  surface 
  tension 
  of 
  

   the 
  liquid 
  used 
  ; 
  this 
  can 
  be 
  measured 
  by 
  counting 
  the 
  number 
  of 
  

   drops 
  formed 
  by 
  5 
  c.c. 
  of 
  the 
  liquid 
  when 
  passing 
  through 
  a 
  pipette 
  

   that 
  allows 
  5 
  c.c. 
  of 
  distilled 
  water 
  to 
  pass 
  out 
  in 
  66 
  drops. 
  For 
  beetles, 
  

   such 
  as 
  Haltica 
  cnnpelophaga 
  , 
  Rhynchites 
  heiuhti 
  and 
  Adoxus 
  vitis 
  a 
  

   soap 
  solution 
  of 
  strength 
  5 
  : 
  10,000 
  is 
  sufficient 
  to 
  kill 
  ; 
  this 
  strength 
  

   corresponds 
  with 
  a 
  surface 
  tension 
  of 
  192 
  drops 
  for 
  5 
  c.c. 
  of 
  the 
  liquid. 
  

   For 
  the 
  webs 
  of 
  Hyponomeuta 
  a 
  solution 
  of 
  1 
  : 
  1,000 
  must 
  be 
  used. 
  

   The 
  addition 
  of 
  soap 
  to 
  insecticides 
  is 
  principally 
  to 
  increase 
  their 
  

   power 
  of 
  moistening 
  the 
  coat 
  of 
  the 
  insect 
  ; 
  to 
  mixtures 
  which 
  con- 
  

   tain 
  acids 
  or 
  inorganic 
  salts 
  it 
  is 
  useless 
  to 
  add 
  soap, 
  as 
  the 
  latter 
  will 
  

   be 
  precipitated. 
  

  

  Nicotin 
  is 
  an 
  important 
  ingredient 
  in 
  many 
  insecticides. 
  In 
  the 
  

   form 
  of 
  tobacco 
  extract 
  it 
  is 
  an 
  important 
  contact 
  poison 
  ; 
  more, 
  

   recently 
  it 
  has 
  been 
  found 
  to 
  be 
  an 
  efficient 
  stomach 
  poison 
  and 
  

   has 
  been 
  used 
  successfully 
  against 
  Clysia 
  ambiguella 
  and 
  PolycJirosis 
  

   hotrana. 
  

  

  Still 
  more 
  important 
  than 
  nicotin 
  as 
  a 
  stomach 
  poison 
  is 
  arsenic, 
  

   in 
  the 
  form 
  of 
  Schweinfurt 
  green 
  and 
  lead 
  arsenate. 
  The 
  question' 
  

   as 
  to 
  whether 
  the 
  fruit 
  is 
  poisoned 
  on 
  trees 
  treated 
  with 
  arsenic 
  com- 
  

   pounds 
  has 
  occupied 
  attention 
  ; 
  probably 
  there 
  is 
  no 
  risk, 
  as 
  the 
  

   spraying 
  is 
  carried 
  out, 
  in 
  the 
  case 
  of 
  vines, 
  for 
  example, 
  early 
  in 
  the 
  

   year, 
  and 
  by 
  the 
  time 
  the 
  fruit 
  appears 
  all 
  traces 
  will 
  have 
  been 
  washed 
  

   away, 
  or 
  what 
  little 
  remains 
  will 
  be 
  in 
  such 
  minute 
  quantities 
  that 
  

   it 
  can 
  be 
  eaten 
  without 
  harm 
  resulting. 
  

  

  The 
  paper 
  concludes 
  with 
  an 
  account 
  of 
  fumigation 
  with 
  hydro- 
  

   cyanic 
  acid, 
  as 
  practised 
  in 
  America. 
  

  

  Sacharov 
  (N.). 
  Biojiorifl 
  BOCKnHuaienbHOM 
  cobkm 
  m 
  o3Mmom 
  no 
  

   HaGmoAeHmM-b 
  B-b 
  TyjibCKoii 
  m 
  iBepcKOH 
  ry6. 
  B-b 
  1909-1910 
  

   rOAaxii. 
  [The 
  biology 
  of 
  Feltia 
  [Agrotis) 
  exclamatioms,^., 
  and 
  of 
  

   Euxoa 
  {Agrotis) 
  segetum, 
  Schiff., 
  according 
  to 
  observations 
  in 
  the 
  

   Govts, 
  of 
  Tula 
  and 
  Tver 
  in 
  1909-1910.]— 
  Fw6Zw/ie^ 
  by 
  the 
  Entom. 
  

   Sta. 
  of 
  the 
  Astrachan 
  Soc. 
  of 
  Fruit-growitig, 
  Gardening, 
  Market- 
  

   Gardening 
  and 
  Field 
  Cultivation, 
  Astrachan, 
  1913, 
  pp. 
  17, 
  1 
  fig. 
  

  

  These 
  observations 
  on 
  Euxoa 
  segetum 
  and 
  Feltia 
  excla)nationis 
  were 
  

   conducted 
  in 
  the 
  district 
  of 
  Novotorzhok 
  of 
  the 
  government 
  of 
  Tver 
  

   and 
  in 
  the 
  district 
  of 
  Bogoroditzk 
  of 
  the 
  government 
  of 
  Tula. 
  In 
  Novo- 
  

   torzhok 
  the 
  moths 
  of 
  both 
  species 
  were 
  on 
  the 
  wing 
  from 
  3rd 
  July 
  to 
  2nd 
  

   August, 
  the 
  maximum 
  being 
  reached 
  about 
  the 
  middle 
  of 
  July. 
  In 
  the 
  

   government 
  of 
  Tula 
  the 
  flying 
  of 
  the 
  moths 
  started, 
  notwithstanding 
  the 
  

   cold 
  weather 
  prevailing, 
  on 
  4th 
  June, 
  reached 
  its 
  maximum 
  on 
  2nd 
  July 
  

   and 
  decreased 
  after 
  28th 
  July. 
  The 
  numbers 
  of 
  E. 
  segetum 
  decreased 
  

   in 
  the 
  first 
  half 
  of 
  July 
  and 
  the 
  females 
  contained 
  fewer 
  eggs 
  ; 
  while 
  

   F. 
  exclamationis 
  increased 
  at 
  this 
  time, 
  and 
  the 
  majority 
  of 
  females 
  

   contained 
  their 
  full 
  complement 
  of 
  eggs. 
  Of 
  the 
  moths 
  captured 
  

   from 
  29th 
  June 
  to 
  7th 
  July, 
  36 
  per 
  cent, 
  were 
  F. 
  ex-clamationis 
  and 
  64 
  

  

  