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  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  young 
  of 
  the 
  San 
  Jose 
  scale 
  are 
  carried 
  short 
  distances 
  by 
  a 
  strong 
  wind, 
  

   and 
  there 
  is 
  no 
  reason 
  why 
  those 
  of 
  other 
  species 
  might 
  not 
  be 
  conveyed 
  

   in 
  the 
  same 
  manner. 
  Evidence 
  of 
  one 
  kind 
  and 
  another 
  has 
  been 
  

   accumulating 
  to 
  show 
  that 
  active 
  young 
  of 
  the 
  scale 
  insects 
  are 
  carried 
  

   by 
  other 
  insects, 
  birds 
  and 
  animals 
  from 
  tree 
  to 
  tree. 
  It 
  is 
  also 
  well 
  

   known 
  that 
  these 
  forms 
  are 
  most 
  readily 
  transported 
  long 
  distances 
  on 
  

   young 
  trees 
  and 
  plants. 
  This 
  means 
  is 
  by 
  far 
  the 
  most 
  important, 
  and 
  

   fortunately 
  is 
  the 
  one 
  most 
  readily 
  controlled. 
  Methods 
  of 
  preventing 
  

   this 
  dissemination 
  will 
  be 
  considered 
  under 
  an 
  appropriate 
  head 
  after 
  the 
  

   discussion 
  of 
  several 
  injurious 
  forms. 
  

  

  Certain 
  species 
  of 
  value. 
  Some 
  Coccidae, 
  or 
  scale 
  insects, 
  are 
  of 
  

   economic 
  importance 
  on 
  account 
  of 
  their 
  products. 
  The 
  well-known 
  

   cochineal 
  is 
  derived 
  from 
  the 
  dried 
  bodies 
  of 
  a 
  scale 
  insect, 
  Coccus 
  

   cacti 
  Linn., 
  which, 
  as 
  is 
  well 
  known, 
  lives 
  on 
  several 
  species 
  of 
  Cac- 
  

   taceaein 
  Mexico. 
  Prof. 
  Comstock 
  states 
  that 
  this 
  insect 
  is 
  also 
  reared 
  

   in 
  India, 
  Spain 
  and 
  other 
  countries. 
  This 
  species 
  or 
  a 
  closely 
  allied 
  form 
  

   is 
  found 
  on 
  wild 
  cactus 
  in 
  Ceylon, 
  as 
  stated 
  by 
  Mr 
  Greeh.^ 
  Another 
  

   species, 
  Tachardia 
  lacca 
  Ker., 
  excretes 
  the 
  substance 
  from 
  which 
  

   is 
  made 
  the 
  'Mac," 
  or 
  shellac, 
  of 
  commerce, 
  and 
  from 
  the 
  insect 
  itself 
  a 
  

   crimson 
  pigment 
  known 
  as 
  "lake" 
  is 
  obtained. 
  This 
  insect 
  lives 
  on 
  

   species 
  of 
  Fie 
  us 
  andonCroton 
  lacciferum. 
  Prof. 
  Comstock 
  

   has 
  described 
  two 
  American 
  species 
  belonging 
  to 
  this 
  genus, 
  

   Tachardia 
  larreae 
  and 
  T. 
  mexicana. 
  The 
  former 
  occurs 
  on 
  

   the 
  creosote 
  plant, 
  Larrea 
  mexicana, 
  a 
  plant 
  growing 
  in 
  the 
  south- 
  

   western 
  part 
  of 
  the 
  United 
  States 
  and 
  in 
  Mexico, 
  and 
  in 
  Prof. 
  Comstock's 
  

   opinion 
  this 
  "lac" 
  insect 
  might 
  prove 
  of 
  economic 
  importance. 
  The 
  

   latter 
  species 
  was 
  found 
  on 
  a 
  twig 
  of 
  mimosa 
  from 
  Tampico 
  (Mex.) 
  It 
  

   is 
  interesting 
  to 
  record 
  that 
  Prof. 
  Cockerell 
  has 
  subsequently 
  described 
  

   four 
  other 
  American 
  species 
  of 
  this 
  genus. 
  The 
  waxy 
  excretion 
  of 
  a 
  

   Chinese 
  scale 
  insect, 
  Ericerus 
  pela 
  Westw. 
  is 
  used 
  in 
  the 
  manufac- 
  

   ture 
  of 
  candles 
  in 
  that 
  country. 
  A 
  near 
  relative 
  of 
  our 
  Gossyparia 
  

   ulmi 
  Geoff., 
  the 
  Go 
  s 
  s 
  ypar 
  ia 
  m 
  an 
  nif 
  er 
  a 
  Hardw., 
  " 
  isfoundupon 
  

   Tamarix 
  mannifera 
  Ehr., 
  a 
  large 
  tree 
  growing 
  upon 
  Mt 
  Sinai, 
  the 
  

   young 
  shoots 
  of 
  which 
  are 
  covered 
  with 
  the 
  females, 
  which, 
  puncturing 
  

   them 
  with 
  their 
  proboscis, 
  cause 
  them 
  to 
  discharge 
  a 
  great 
  quantity 
  of 
  a 
  

   gummy 
  secretion, 
  which 
  quickly 
  hardens 
  and 
  drops 
  from 
  the 
  tree, 
  when 
  

   it 
  is 
  collected 
  by 
  the 
  natives, 
  who 
  regard 
  it 
  as 
  the 
  real 
  manna 
  of 
  the 
  

   Israelites." 
  2 
  

  

  1 
  Green, 
  E. 
  E. 
  Coccidae 
  of 
  Ceylon. 
  1899. 
  p. 
  3. 
  

  

  2 
  Westwood, 
  J. 
  O. 
  Introduction 
  to 
  the 
  modern 
  classification 
  of 
  Insects. 
  2 
  : 
  449. 
  

  

  