﻿416 
  

  

  zimmermanni, 
  Newst., 
  have 
  also 
  been 
  observed 
  on 
  this 
  tree. 
  Manihot 
  

   has 
  been 
  attacked 
  by 
  Thrips, 
  but 
  to 
  no 
  considerable 
  extent 
  and 
  the 
  

   affected 
  trees 
  quickly 
  recover 
  after 
  the 
  disappearance 
  of 
  the 
  pest. 
  

  

  Bodkin 
  (G. 
  E.). 
  The 
  Scale-Insects 
  of 
  British 
  Guiana. 
  — 
  Jl 
  Bd. 
  Agric. 
  

   Brit. 
  Guiana, 
  Georgetown, 
  vii, 
  no. 
  3, 
  Jan. 
  1914, 
  pp. 
  106-124. 
  

   [Received 
  17th 
  March 
  1914.] 
  

  

  The 
  author 
  points 
  out 
  that 
  references 
  to 
  the 
  Coccidae 
  of 
  British 
  

   Guiana 
  are 
  scanty, 
  and 
  the 
  collection 
  here 
  recorded 
  has 
  been 
  formed 
  

   by 
  him 
  since 
  1911 
  and 
  is 
  fairly 
  representative. 
  A 
  further 
  and 
  more 
  

   complete 
  list 
  will 
  be 
  published 
  later. 
  The 
  majority 
  of 
  the 
  determina- 
  

   tions 
  were 
  made 
  through 
  the 
  Imperial 
  Bureau 
  of 
  Entomology 
  by 
  

   Professor 
  Newstead. 
  The 
  classification 
  adhered 
  to 
  is 
  that 
  adopted 
  

   by 
  Mrs. 
  Fernald 
  in 
  her 
  catalogue. 
  Scale-insects, 
  popularly 
  known 
  

   in 
  Demerara 
  as 
  " 
  blight," 
  are 
  one 
  of 
  the 
  worst 
  agricultural 
  pests 
  

   in 
  British 
  Guiana, 
  where 
  some 
  half-dozen 
  species, 
  widely 
  distributed 
  

   and 
  capable 
  of 
  existing 
  on 
  a 
  variety 
  of 
  cultivated 
  plants, 
  are 
  annually 
  

   responsible 
  for 
  an 
  enormous 
  amount 
  of 
  damage. 
  The 
  Hymenopterous 
  

   parasites 
  of 
  the 
  Coccids 
  will 
  be 
  dealt 
  with 
  later. 
  Other 
  natural 
  

   enemies 
  include 
  certain 
  Lepidopterous 
  larvae, 
  Coccinellid 
  beetles 
  in 
  

   their 
  larval 
  and 
  adult 
  stages, 
  fungi, 
  and 
  the 
  larvae 
  of 
  lacewing 
  flies 
  

   (Neuroptera). 
  Blastohasis 
  lecaniella, 
  Busck, 
  and 
  two 
  new 
  Pyrahds, 
  

   Vitula 
  bodkini, 
  Dyar, 
  and 
  Vitula 
  toboga, 
  Dyar, 
  are 
  the 
  three 
  species 
  

   of 
  coccophagous 
  Lepidopterous 
  larvae 
  found 
  in 
  British 
  Guiana. 
  Of 
  

   the 
  CocciNELLiDAE, 
  two 
  spccics 
  which 
  destroy 
  Aspidiotus 
  destructor. 
  

   Sign., 
  have 
  recently 
  been 
  described, 
  viz.: 
  — 
  Cryptognatha 
  nodiceps, 
  

   Mshl., 
  and 
  Azya 
  trinitatis, 
  Mshl. 
  Azya 
  pontbrianti, 
  Muls., 
  is 
  pre- 
  

   daceous 
  on 
  S. 
  hemispJiaerica, 
  Targ. 
  A 
  number 
  of 
  other 
  species 
  await 
  

   determination. 
  Two 
  species 
  of 
  entomophagous 
  fungi 
  are 
  frequently 
  

   found 
  attacking 
  colonies 
  of 
  scale-insects, 
  viz., 
  the 
  red-headed 
  fungus 
  

   {Sphaerostilbe 
  coccophila,T\il.) 
  and 
  the 
  shield 
  scale 
  fungus 
  (Cephalosporium 
  

   lecanii) 
  . 
  Parasitic 
  fungi 
  are 
  especially 
  valuable 
  in 
  the 
  citrus 
  cultivations 
  

   situated 
  inland. 
  Local 
  experience 
  has 
  shown 
  that 
  scale 
  infestation 
  

   may 
  be 
  controlled 
  by 
  two 
  really 
  efficient, 
  simple, 
  cheap 
  and 
  easily 
  

   prepared 
  washes 
  within 
  the 
  reach 
  of 
  any 
  cultivator, 
  viz 
  : 
  — 
  kerosene 
  

   emulsion 
  and 
  resin 
  compound. 
  For 
  use 
  against 
  the 
  softer-bodied 
  

   scale-insects 
  (Aspidiotus 
  destructor, 
  mealy 
  bug, 
  croton 
  bug, 
  etc.) 
  the 
  

   following 
  is 
  a 
  good 
  formula 
  : 
  Kerosene 
  oil 
  2 
  gals., 
  water 
  1 
  gal., 
  soap 
  

   J 
  lb. 
  The 
  soap 
  is 
  first 
  dissolved 
  in 
  hot 
  water, 
  and 
  the 
  kerosene 
  added 
  

   while 
  the 
  solution 
  is 
  still 
  hot, 
  the 
  mixture 
  being 
  well 
  stirred 
  so 
  as 
  to 
  

   form 
  a 
  good 
  emulsion. 
  For 
  use, 
  6 
  gals, 
  of 
  water 
  are 
  added 
  and 
  the 
  

   whole 
  is 
  thoroughly 
  mixed. 
  Resin 
  compound 
  is 
  an 
  excellent 
  spray 
  

   for 
  the 
  hard-bodied 
  scales, 
  though 
  it 
  may 
  be 
  used 
  with 
  good 
  results 
  

   against 
  any 
  kind 
  of 
  Coccid. 
  It 
  is 
  prepared 
  as 
  follows 
  : 
  Resin 
  

   (powdered) 
  3 
  lb., 
  ordinary 
  washing 
  soda 
  2 
  lb. 
  These 
  substances 
  are 
  

   thoroughly 
  mixed 
  and 
  dissolved 
  by 
  heat 
  in 
  a 
  large 
  vessel 
  in 
  about 
  a 
  

   gallon 
  of 
  water, 
  and 
  water 
  up 
  to 
  4 
  gals, 
  is 
  gradually 
  added. 
  Boihng 
  

   is 
  continued 
  till 
  the 
  solution 
  turns 
  a 
  clear 
  brown 
  colour. 
  One 
  part 
  

   of 
  this 
  mixture 
  is 
  diluted 
  with 
  4 
  parts 
  of 
  water 
  for 
  use. 
  In 
  the 
  case 
  of 
  

   either 
  of 
  these 
  sprays 
  several 
  applications 
  are 
  necessary, 
  at 
  weekly 
  

   intervals, 
  till 
  the 
  fohage, 
  branches, 
  etc., 
  appear 
  clean. 
  The 
  article 
  

  

  