﻿405 
  

  

  PicARD 
  (F.). 
  Rapport 
  sur 
  la 
  Cochylis 
  et 
  I'Eudemis 
  dans 
  le 
  Midi 
  de 
  la 
  

   France. 
  [Report 
  on 
  Clysia 
  and 
  Polychrosis 
  in 
  the 
  South 
  of 
  

   France.] 
  — 
  Ann. 
  die 
  Service 
  des 
  Epiphyties 
  (1912), 
  Paris, 
  1913, 
  

   pp. 
  352-364. 
  [Received 
  18th 
  Feb. 
  1914.] 
  

  

  It 
  is 
  certain 
  that 
  the 
  disappearance 
  of 
  Clysia 
  ambiyuella 
  has 
  favoured 
  

   the 
  tendency 
  of 
  Polychrosis 
  botrana 
  to 
  spread. 
  Experiments 
  made 
  

   to 
  determine 
  the 
  action 
  of 
  heat 
  on 
  the 
  winter 
  pupa, 
  showed 
  that 
  

   Polychrosis 
  cocoons 
  submitted 
  to 
  a 
  temperature 
  of 
  79°-82° 
  Fahr. 
  

   produced 
  adults 
  about 
  4 
  months 
  before 
  the 
  normal 
  time. 
  The 
  author 
  

   noticed 
  Polychrosis 
  on 
  Arbutus 
  unedo 
  and 
  on 
  Daphne 
  gnidiwn, 
  both 
  

   of 
  which 
  seem 
  very 
  suitable 
  food-plants, 
  especially 
  the 
  former. 
  It 
  was 
  

   also 
  found 
  on 
  Zizyphus 
  vulgaris, 
  w^hich 
  appears 
  to 
  excite 
  the 
  silk 
  

   producing 
  glands, 
  for 
  the 
  cocoons 
  were 
  about 
  twice 
  the 
  size 
  of 
  those 
  

   found 
  on 
  the 
  vine, 
  though 
  of 
  the 
  same 
  texture. 
  The 
  carnivorous 
  

   Acarid 
  Pediculoides 
  ventricosus 
  speedily 
  kills 
  both 
  Clysia 
  and 
  Polychrosis 
  

   larvae 
  and 
  seems 
  suitable 
  for 
  use 
  against 
  the 
  first 
  generation 
  when 
  

   protecting 
  vine-arbours 
  or 
  a 
  limited 
  number 
  of 
  stocks. 
  Parasitic 
  

   fungi 
  were 
  tried 
  without 
  success. 
  Attempts 
  to 
  infect 
  Polychrosis 
  with 
  

   micro-organisms, 
  those 
  of 
  " 
  pebrine 
  " 
  and 
  " 
  grasserie" 
  were 
  successful, 
  

   but 
  infection 
  was 
  difficult 
  to 
  bring 
  about 
  and 
  lacked 
  virulence. 
  In 
  

   the 
  course 
  of 
  experiments 
  with 
  various 
  methods 
  of 
  winter 
  treatment, 
  

   proof 
  was 
  obtained 
  that 
  the 
  newly 
  hatched 
  moth 
  is 
  nearly 
  always 
  

   incapable 
  of 
  passing 
  through 
  a 
  layer 
  of 
  light 
  earth 
  or 
  fine 
  sand 
  two-fifths 
  

   of 
  an 
  inch 
  thick. 
  A 
  compact 
  soil, 
  more 
  or 
  less 
  clayey, 
  must 
  therefore 
  

   be 
  quite 
  impassable. 
  Submersion 
  is 
  efiicacious 
  when 
  the 
  entire 
  stock, 
  

   or 
  the 
  greater 
  part 
  of 
  it, 
  can 
  be 
  placed 
  under 
  w^ater. 
  Where 
  big 
  

   branches 
  emerge, 
  submersion 
  is 
  not 
  efficacious, 
  and 
  may 
  sometimes 
  

   prove 
  injurious, 
  for 
  the 
  pupae 
  located 
  on 
  the 
  emerging 
  branches 
  are 
  

   favoured 
  by 
  the 
  dampness 
  of 
  the 
  soil. 
  This 
  may 
  be 
  avoided 
  by 
  

   decorticating 
  the 
  branches 
  above 
  the 
  water-line 
  as 
  soon 
  as 
  the 
  sur- 
  

   rounding 
  soil 
  permits. 
  Submersion 
  may, 
  however, 
  be 
  bad 
  from 
  

   another 
  point 
  of 
  view 
  : 
  Cacoecia 
  costana 
  (the 
  geflammte 
  Traubenivickler 
  

   of 
  the 
  Germans) 
  which 
  is 
  omnivorous 
  and 
  attracted 
  by 
  moisture, 
  

   is 
  compelled 
  by 
  submersion 
  to 
  resort 
  to 
  the 
  vine, 
  as 
  other 
  low-lying 
  

   food-plants 
  are 
  under 
  water. 
  Watering 
  the 
  vineyards 
  is 
  a 
  practice 
  

   which 
  cannot 
  be 
  dispensed 
  with 
  in 
  the 
  South 
  of 
  France, 
  but 
  Clysia 
  

   moths 
  concentrate 
  on 
  vineyards 
  which 
  have 
  been 
  watered 
  and 
  damage 
  

   them 
  to 
  a 
  very 
  noticeable 
  extent. 
  The 
  only 
  plan 
  is 
  to 
  delay 
  watering 
  

   as 
  much 
  as 
  possible 
  and 
  ascertain 
  first 
  that 
  the 
  fiight 
  of 
  the 
  moths 
  has 
  

   finished. 
  This 
  may 
  be 
  done 
  by 
  setting 
  a 
  few 
  light 
  traps. 
  Too 
  pro- 
  

   longed 
  a 
  delay 
  may 
  be 
  dangerous, 
  as 
  then 
  the 
  watering 
  might 
  coincide 
  

   with 
  the 
  third 
  Polychrosis 
  flight. 
  The 
  author 
  did 
  not 
  obtain 
  good 
  

   results 
  with 
  either 
  bait 
  or 
  light 
  traps, 
  though 
  it 
  was 
  shown 
  that 
  more 
  

   females 
  are 
  attracted 
  by 
  bait 
  and 
  more 
  males 
  by 
  light. 
  Spring 
  

   insecticide 
  treatment 
  was 
  incomplete, 
  but 
  showed 
  that 
  both 
  lead 
  

   arsenate 
  and 
  sodium 
  arsenate 
  are 
  of 
  use. 
  The 
  latter 
  substance, 
  

   at 
  a 
  strength 
  of 
  1 
  per 
  1,000 
  in 
  water, 
  does 
  not 
  cause 
  injury 
  to 
  the 
  

   plants 
  and 
  appears 
  quite 
  as 
  efiicacious 
  as 
  lead 
  arsenate. 
  Summer 
  

   insecticide 
  treatment 
  was 
  carried 
  out 
  on 
  a 
  larger 
  scale. 
  None 
  of 
  the 
  

   products 
  tested 
  gave 
  satisfaction, 
  though 
  lead 
  arsenate 
  and 
  sodium 
  

   arsenate 
  showed 
  an 
  efficiency 
  of 
  about 
  50 
  per 
  cent, 
  and 
  the 
  latter 
  

   at 
  a 
  strength 
  of 
  1 
  per 
  1,000 
  proved 
  no 
  less 
  efficacious 
  than 
  the 
  former. 
  

  

  