﻿703 
  

  

  obtain 
  the 
  killing 
  temperature 
  is 
  often 
  due 
  to 
  lack 
  of 
  sufficient 
  radiating 
  

   surface 
  to 
  overcome 
  the 
  moisture. 
  For 
  the 
  sake 
  of 
  economy, 
  a 
  dry, 
  

   warm 
  day 
  should 
  be 
  chosen 
  on 
  which 
  to 
  heat 
  the 
  average 
  flour 
  mill. 
  

   Maximum 
  economy 
  of 
  heating 
  will 
  be 
  obtained 
  by 
  using 
  a 
  steam 
  

   pressure 
  of 
  about 
  50-60 
  lb., 
  since 
  this 
  gives 
  the 
  temperature 
  necessary 
  

   to 
  kill. 
  Experiments 
  showed 
  that 
  most 
  species 
  of 
  insects 
  were 
  killed 
  

   at 
  a 
  slightly 
  lower 
  temperature 
  when 
  using 
  moist 
  heat 
  than 
  when 
  

   using 
  dry. 
  The 
  rice 
  weevil, 
  C. 
  oryzae, 
  was 
  especially 
  susceptible 
  to 
  

   heat 
  in 
  a 
  moist 
  atmosphere, 
  being 
  always 
  killed 
  at 
  3° 
  C. 
  to 
  4° 
  C, 
  

   below 
  the 
  temperature 
  required 
  in 
  dry 
  air. 
  As 
  a 
  rule 
  the 
  egg 
  stage 
  

   was 
  the 
  first 
  to 
  be 
  destroyed. 
  Silvanus 
  surinamensis 
  was 
  not 
  much 
  

   more 
  susceptible 
  to 
  moist 
  than 
  dry 
  heat. 
  The 
  egg 
  stage 
  was 
  killed 
  

   at 
  4:4:°-45° 
  C, 
  the 
  larvae, 
  pupae 
  and 
  adults 
  at 
  46°-48° 
  C. 
  Cathartus 
  

   advena 
  is 
  killed 
  at 
  1° 
  C. 
  lower 
  temperature 
  in 
  moist 
  than 
  in 
  dry 
  heat, 
  

   and 
  like 
  S. 
  surinamensis, 
  does 
  not 
  always 
  recover 
  from 
  the 
  effects 
  of 
  

   dry 
  heat, 
  but 
  dies 
  several 
  hours 
  or 
  days 
  after 
  the 
  test. 
  The 
  effects 
  

   of 
  heat 
  on 
  C. 
  quadricollis, 
  Guer., 
  (gemellatus) 
  seemed 
  to 
  be 
  similar 
  to 
  

   those 
  on 
  C. 
  advena. 
  The 
  adult 
  beetles 
  of 
  LaemopJdoeus 
  minutus 
  

   require 
  a 
  temperature 
  of 
  nearly 
  50° 
  C 
  ; 
  the 
  larvae 
  and 
  pupae 
  were 
  

   killed 
  by 
  48° 
  0.-49° 
  C, 
  and 
  no 
  eggs 
  hatched 
  after 
  being 
  heated 
  up 
  to 
  

   45° 
  C. 
  The 
  young 
  larva 
  of 
  Trogoderma 
  ornatum 
  is 
  the 
  most 
  resistant 
  

   of 
  the 
  cereal 
  pests 
  so 
  far 
  tested, 
  the 
  killing 
  temperature 
  being 
  from 
  

   52-53° 
  C. 
  ; 
  the 
  beetles, 
  pupae 
  and 
  full 
  grown 
  larvae 
  were 
  killed 
  by 
  

   48-50° 
  C. 
  Moist 
  atmosphere 
  at 
  48° 
  C. 
  to 
  50° 
  C. 
  was 
  fatal 
  to 
  the 
  

   beetles, 
  pupae 
  and 
  full-grown 
  larvae, 
  but 
  was 
  no 
  more 
  effective 
  than 
  

   a 
  dry 
  atmosphere 
  at 
  similar 
  temperatures. 
  

  

  AiNSLiE 
  (G. 
  G.). 
  The 
  Western 
  Corn 
  Root 
  Worm. 
  — 
  Jl. 
  Econ. 
  Entam., 
  

   Concord, 
  vii, 
  no. 
  4, 
  August 
  1914, 
  pp. 
  322-324. 
  

  

  The 
  presence 
  of 
  Diabrotica 
  longicornis, 
  especially 
  in 
  the 
  Gulf 
  and 
  

   S. 
  Atlantic 
  States, 
  should 
  be 
  watched 
  for 
  and 
  reported. 
  Along 
  the 
  

   Arkansas, 
  Mississippi, 
  Ohio 
  and 
  other 
  rivers 
  are 
  large 
  areas 
  of 
  rich 
  

   land 
  subject 
  to 
  an 
  almost 
  certain 
  annual 
  inundation. 
  The 
  use 
  of 
  the 
  

   one 
  remedy 
  known 
  for 
  this 
  pest, 
  that 
  of 
  crop 
  rotation, 
  is 
  here 
  impossible, 
  

   and 
  unless 
  some 
  crop 
  can, 
  occasionally 
  at 
  least, 
  take 
  the 
  place 
  of 
  maize, 
  

   or 
  other 
  method 
  of 
  control 
  be 
  found, 
  great 
  damage 
  will 
  continue 
  to 
  

   be 
  done. 
  The 
  eggs 
  are 
  laid 
  in 
  late 
  July, 
  August 
  and 
  September 
  in 
  

   the 
  ground 
  round 
  the 
  roots. 
  They 
  hatch 
  in 
  late 
  May 
  or 
  early 
  June 
  

   of 
  the 
  following 
  year, 
  and 
  the 
  larvae 
  are 
  most 
  injurious 
  in 
  late 
  June 
  

   and 
  early 
  July, 
  especially 
  if 
  there 
  is 
  a 
  drought. 
  The 
  beetles 
  begin 
  

   to 
  appear 
  in 
  July, 
  and, 
  if 
  sufficiently 
  numerous, 
  cause 
  serious 
  additional 
  

   injury. 
  

  

  McGregor 
  (E. 
  A.). 
  Red 
  Spider 
  Control. 
  — 
  Jl. 
  Econ. 
  Entom., 
  Concord, 
  

   vii, 
  no. 
  4, 
  August 
  1914, 
  pp. 
  324-336. 
  

  

  Tetranychus 
  bimaculatus 
  and 
  its 
  control 
  are 
  here 
  discussed 
  [see 
  this 
  

   Review, 
  Ser. 
  A, 
  i, 
  pp. 
  240, 
  241, 
  353]. 
  The 
  so-called 
  '' 
  red 
  spider 
  " 
  

   is 
  commonly 
  found 
  on 
  the 
  English 
  violet 
  or 
  the 
  cultivated 
  one, 
  which 
  

   generally 
  serves 
  as 
  its 
  winter 
  host, 
  as 
  well 
  as 
  on 
  many 
  cultivated 
  

   flowers, 
  cotton, 
  tomato 
  and 
  Jerusalem 
  oakweed 
  ; 
  infestations 
  in 
  

   towns 
  nearly 
  always 
  arise 
  from 
  cultivated 
  violets, 
  those 
  in 
  the 
  country 
  

   from 
  the 
  pokeweed. 
  A 
  particular 
  case 
  of 
  origin 
  from 
  pokeweed 
  is 
  

   described, 
  where 
  an 
  infestation 
  was 
  seen 
  to 
  extend 
  from 
  a 
  centre 
  

  

  