﻿21 
  

  

  The 
  author 
  states 
  that 
  the 
  factors 
  which 
  led 
  to 
  the 
  study 
  of 
  the 
  sub- 
  

   ject 
  are 
  : 
  — 
  (1) 
  It 
  is 
  the 
  most 
  important 
  problem 
  before 
  the 
  farmers 
  

   and 
  fruit-growers 
  of 
  to-day 
  ; 
  (2) 
  for 
  some 
  one 
  or 
  more 
  reasons 
  not 
  

   clear 
  to 
  us, 
  our 
  knowledge 
  of 
  sprays 
  and 
  their 
  effects 
  is 
  very 
  unsatis- 
  

   factory 
  ; 
  (3) 
  while 
  our 
  commercial 
  insecticides 
  are 
  more 
  or 
  less 
  stable 
  

   under 
  certain 
  ideal 
  conditions, 
  the 
  results 
  obtained 
  from 
  their 
  use 
  are 
  

   too 
  variable 
  for 
  us 
  to 
  make 
  definite 
  regulations 
  ; 
  (4) 
  the 
  economy 
  of 
  

   spraying 
  and 
  the 
  numerous 
  new 
  sprays 
  on 
  the 
  market 
  at 
  the 
  present 
  

   time 
  demand 
  an 
  entirely 
  new 
  investigation 
  of 
  the 
  subject. 
  

  

  The 
  results 
  are 
  summarised 
  as 
  follows 
  : 
  — 
  Arsenite 
  of 
  zinc 
  acts 
  more 
  

   quickly, 
  and 
  remains 
  in 
  suspension 
  better 
  than 
  arsenate 
  of 
  lead, 
  acid 
  

   or 
  non-acid 
  ; 
  acid 
  arsenate 
  of 
  lead 
  was 
  superior 
  in 
  these 
  respects 
  to 
  

   the 
  non-acid 
  ; 
  the 
  non-acid 
  is 
  slow, 
  but 
  finally 
  kills 
  ; 
  lime-sulphur 
  

   <:lid 
  not 
  prove 
  of 
  much 
  value 
  as 
  a 
  stomach 
  poison, 
  and 
  when 
  mixed 
  

   "with 
  arsenicals 
  seems 
  to 
  retard 
  their 
  action 
  ; 
  Ume-sulphur 
  probably 
  

   acts 
  as 
  a 
  repellent 
  to 
  biting 
  insects 
  as 
  Bordeaux 
  mixture 
  does 
  against 
  

   the 
  potato 
  flea-beetle 
  ; 
  very 
  young 
  caterpillars 
  placed 
  on 
  twigs 
  which 
  

   had 
  been 
  sprayed 
  with 
  lime-sulphur 
  did 
  not 
  feed, 
  and 
  eventually 
  

   died 
  ; 
  half-grown 
  larvae 
  did 
  feed 
  to 
  some 
  extent, 
  and 
  when 
  transferred 
  

   to 
  unsprayed 
  twigs 
  developed 
  normally. 
  

  

  AViNSLow 
  (R. 
  M.). 
  The 
  Economic 
  side 
  of 
  Pest-Control. 
  — 
  Proc. 
  Entom, 
  

   Soc. 
  Br. 
  Columbia, 
  Victoria, 
  B.C., 
  no. 
  3, 
  N.S., 
  1913, 
  pp. 
  17-21. 
  

  

  For 
  the 
  Province, 
  expenditure 
  on 
  the 
  control 
  of 
  pests 
  for 
  1913 
  is 
  

   estimated 
  at 
  21,000 
  dollars 
  for 
  material, 
  20,000 
  for 
  application, 
  and 
  

   12,500 
  for 
  25 
  per 
  cent, 
  of 
  equipment 
  costs. 
  

  

  The 
  paper 
  also 
  embodies 
  a 
  report 
  on 
  the 
  cost 
  of 
  manufacturing 
  

   lime-sulphur 
  at 
  Okanagan. 
  With 
  material 
  at 
  wholesale 
  prices 
  and 
  

   freight 
  at 
  car-load 
  rates, 
  the 
  commercial 
  article 
  delivered 
  at 
  Okanagan 
  

   Points 
  costs 
  about 
  £2 
  7s. 
  per 
  40 
  gallon 
  barrel 
  of 
  625 
  lbs. 
  Provided 
  

   the 
  same 
  conditions 
  obtain, 
  the 
  cost 
  of 
  manufacturing 
  at 
  Okanagan 
  

   is 
  about 
  £1 
  Os. 
  lOd. 
  When 
  buying 
  material 
  in 
  less 
  than 
  car-load 
  lots 
  

   it 
  would 
  rise 
  to 
  £1 
  8s. 
  lOd. 
  approximately. 
  There 
  would 
  be, 
  in 
  

   addition, 
  the 
  cost 
  of 
  a 
  hydrometer 
  (4s. 
  2d.)' 
  and 
  the 
  first 
  cost 
  of 
  

   the 
  boiling 
  plant, 
  which 
  on 
  a 
  one-barrel 
  scale 
  need 
  not 
  be 
  over 
  

   £2 
  9s. 
  5d., 
  and 
  might 
  be 
  kept 
  as 
  low 
  as 
  12s. 
  6d. 
  or 
  16s.. 
  8d. 
  The 
  

   product 
  should 
  test 
  about 
  20° 
  Beaume, 
  that 
  is, 
  not 
  quite 
  so 
  strong 
  

   as 
  the 
  commercial 
  one 
  which 
  tests 
  32J° 
  Beaume. 
  Under 
  proper 
  

   conditions 
  several 
  dollars 
  per 
  barrel 
  might 
  be 
  saved 
  ; 
  but 
  on 
  the 
  

   small 
  scale, 
  especially 
  with 
  inexperience, 
  the 
  saving 
  would 
  be 
  more 
  

   apparent 
  than 
  real. 
  

  

  Treherne 
  (R. 
  C). 
  Methods 
  of 
  taking 
  insect 
  records 
  in 
  the 
  field. 
  

   — 
  Proc. 
  Entom. 
  Soc. 
  Br. 
  Columbia, 
  Victoria, 
  B.C., 
  no. 
  3, 
  N.S., 
  

   1913, 
  pp. 
  21-24. 
  

  

  Without 
  claiming 
  originality, 
  the 
  author 
  puts 
  forward 
  several 
  

   suggestions 
  he 
  has 
  found 
  useful. 
  To 
  determine 
  percentage 
  of 
  infes- 
  

   tation 
  : 
  select 
  5 
  typical 
  locations 
  in 
  the 
  field 
  to 
  be 
  examined, 
  and 
  from 
  

   them 
  a 
  typical 
  row, 
  tree, 
  or 
  plant 
  to 
  be 
  inspected. 
  Then 
  count 
  50 
  

   plants, 
  buds, 
  fruit, 
  or 
  leaves, 
  as 
  desired, 
  and 
  examine 
  carefully 
  for 
  

  

  