﻿651 
  

  

  of 
  larvae 
  wliich 
  had. 
  reached 
  the 
  trees 
  after 
  the 
  spraying. 
  When 
  this 
  

   orchard 
  was 
  visited 
  in 
  March 
  1912 
  the 
  general 
  condition 
  of 
  the 
  trees 
  

   was 
  very 
  much 
  improved, 
  though 
  some 
  of 
  the 
  scale-insects 
  remained. 
  

   The 
  cost 
  of 
  this 
  remedy 
  amounts 
  to 
  about 
  6d. 
  per 
  tree. 
  Experiments 
  

   with 
  green 
  soap 
  and 
  with 
  iron 
  sulphate 
  were 
  undertaken 
  simultaneously 
  

   in 
  the 
  district 
  of 
  Kishinev 
  in 
  November 
  1913. 
  At 
  this 
  time 
  many 
  

   leaves 
  still 
  remained 
  on 
  the 
  plum 
  trees 
  attacked 
  by 
  scale-insects, 
  

   though 
  not 
  on 
  other 
  fruit 
  trees, 
  and 
  many 
  of 
  the 
  fallen 
  leaves 
  contained 
  

   larvae 
  of 
  E. 
  cerasi. 
  Three 
  solutions 
  of 
  green 
  soap 
  were 
  prepared, 
  

   containing 
  respectively 
  J, 
  1 
  and 
  2 
  lb. 
  of 
  soap 
  dissolved 
  in 
  about 
  2J 
  

   gallons 
  of 
  water, 
  while 
  the 
  strength 
  of 
  iron 
  sulphate 
  was 
  5 
  per 
  cent. 
  

   The 
  examination 
  of 
  the 
  sprayed 
  trees 
  had 
  to 
  be 
  left 
  till 
  the 
  following 
  

   February, 
  1914, 
  when 
  branches 
  from 
  the 
  sprayed 
  trees 
  were 
  kept 
  in 
  

   the 
  laboratory 
  under 
  artificial 
  conditions. 
  The 
  larvae 
  from 
  the 
  trees 
  

   sprayed 
  with 
  5 
  per 
  cent, 
  iron 
  sulphate 
  and 
  with 
  J 
  and 
  1 
  lb. 
  of 
  green 
  

   soap 
  were 
  unharmed, 
  while 
  those 
  from 
  the 
  trees 
  sprayed 
  with 
  2 
  lb. 
  

   of 
  green 
  soap 
  perished. 
  Thus 
  only 
  the 
  latter 
  solution 
  can 
  be 
  recom- 
  

   mended 
  as 
  efficient, 
  its 
  cost 
  amounting 
  to 
  2d. 
  per 
  tree. 
  As 
  this 
  

   solution 
  does 
  not 
  injure 
  the 
  swelled 
  buds, 
  a 
  late 
  spraying 
  is 
  advisable, 
  

   for 
  most 
  of 
  the 
  larvae 
  are 
  then 
  on 
  the 
  trees. 
  An 
  experiment 
  with 
  

   kerosene 
  water 
  by 
  means 
  of 
  the 
  newly 
  invented 
  " 
  kerovator 
  " 
  of 
  the 
  

   system 
  of 
  " 
  Platz 
  " 
  and 
  the 
  sprayer 
  used 
  are 
  described. 
  The 
  sprayer 
  

   is 
  filled 
  with 
  water 
  and 
  is 
  connected 
  by 
  means 
  of 
  a 
  hose 
  with 
  the 
  

   kerovator 
  filled 
  with 
  kerosene 
  and 
  fixed 
  to 
  a 
  belt. 
  The 
  percentage 
  

   of 
  the 
  solution 
  in 
  the 
  apparatus 
  should 
  be 
  tested 
  before 
  use. 
  The 
  

   experiment 
  was 
  conducted 
  on 
  9th 
  March 
  1914, 
  the 
  strength 
  of 
  the 
  

   solution 
  varying 
  from 
  1 
  per 
  cent, 
  to 
  21 
  per 
  cent. 
  As 
  at 
  the 
  time 
  of 
  the 
  

   experiment 
  some 
  larvae 
  were 
  still 
  hibernating 
  amongst 
  the 
  fallen 
  leaves, 
  

   trap 
  belts 
  were 
  put 
  on 
  the 
  trees 
  so 
  as 
  to 
  prevent 
  these 
  larvae 
  from 
  

   reaching 
  them 
  after 
  the 
  spraying. 
  Examination 
  of 
  branches 
  taken 
  

   from 
  the 
  sprayed 
  trees 
  and 
  kept 
  in 
  the 
  laboratory 
  showed 
  that 
  1 
  per 
  

   cent, 
  and 
  2 
  per 
  cent, 
  of 
  this 
  solution 
  were 
  ineffective 
  while 
  all 
  stronger 
  

   solutions 
  destroyed 
  the 
  larvae. 
  On 
  branches 
  taken 
  from 
  trees 
  without 
  

   trap 
  belts 
  on 
  them 
  a 
  small 
  number 
  of 
  living 
  larvae 
  were 
  found, 
  irrespec- 
  

   tive 
  of 
  the 
  strength 
  of 
  the 
  solution 
  apphed, 
  showing 
  that 
  they 
  must 
  

   have 
  reached 
  the 
  tree 
  after 
  spraying. 
  The 
  cost 
  of 
  this 
  remedy 
  is 
  only 
  

   about 
  IJd. 
  per 
  tree, 
  allowing 
  5| 
  lb. 
  of 
  kerosene 
  for 
  6 
  trees. 
  Thus 
  it 
  is 
  

   the 
  cheapest 
  and 
  at 
  the 
  same 
  time 
  also 
  the 
  most 
  handy 
  remedy, 
  as 
  

   kerosene 
  can 
  be 
  obtained 
  everywhere, 
  which 
  is 
  not 
  always 
  the 
  case 
  

   with 
  carbolineum 
  and 
  green 
  soap. 
  

  

  Rutherford 
  (A.). 
  Leaf 
  Miner 
  of 
  Citrus 
  {Phyllocnistis 
  citrella, 
  Stainton). 
  

   — 
  Trop. 
  Agric, 
  Peradeniya, 
  xliii, 
  no. 
  1 
  , 
  July 
  1914, 
  pp. 
  49-50. 
  

  

  The 
  larvae 
  of 
  the 
  Tineid, 
  Phyllocnistis 
  citrella, 
  attack 
  citrus 
  trees, 
  

   mining 
  the 
  young 
  twigs 
  and 
  leaves, 
  and 
  the 
  folds 
  thus 
  induced 
  may 
  

   be 
  subsequently 
  tenanted 
  by 
  Psendococcus 
  spp., 
  which 
  in 
  Ceylon, 
  

   however, 
  are 
  attacked 
  by 
  the 
  Lycaenid, 
  Spalgis 
  epiiis, 
  West., 
  and 
  

   a 
  Cecidom)did, 
  Diadiplosis 
  coccidivora, 
  Felt. 
  The 
  caterpillars 
  of 
  

   P. 
  citrella 
  are 
  subject 
  to 
  the 
  attack 
  of 
  small, 
  black 
  Chalcids, 
  the 
  larvae 
  

   of 
  which 
  feed 
  externally 
  on 
  them. 
  These 
  parasites 
  do 
  not 
  appear 
  to 
  

   constitute 
  an 
  effective 
  control 
  and 
  the 
  citrus-grower 
  should 
  be 
  on 
  the 
  

   look 
  out 
  for 
  the 
  first 
  signs 
  of 
  attack, 
  and 
  spray 
  with 
  tobacco 
  extract. 
  

  

  