﻿SCALE 
  INSECTS 
  OF 
  IMPORTANCE 
  307 
  

  

  marked 
  adult 
  female 
  scale 
  reveals 
  the 
  following 
  characteristics. 
  It 
  is 
  al- 
  

   most 
  2 
  mm, 
  or 
  -1^^ 
  inch, 
  in 
  diameter, 
  nearly 
  circular, 
  grayish, 
  with 
  a 
  cen- 
  

   tral 
  darker 
  nipple 
  surrounded 
  by 
  one 
  or 
  more 
  rather 
  well-defined 
  yellowish 
  

   rings 
  (fig. 
  9). 
  The 
  smaller 
  scales 
  are 
  nearly 
  black, 
  with 
  a 
  central 
  nipple, 
  

   and 
  one 
  or 
  two 
  grayish 
  rings 
  as 
  represented 
  in 
  figure 
  13. 
  The 
  largest 
  

   scales 
  are 
  just 
  about 
  the 
  size 
  of 
  the 
  head 
  of 
  an 
  ordinary 
  pin, 
  while 
  the 
  

   smaller 
  ones 
  are 
  mere 
  dots, 
  as 
  represented 
  by 
  the 
  black 
  specks 
  on 
  the 
  

   twig, 
  figure 
  5. 
  Sometimes 
  the 
  female 
  scales 
  have 
  a 
  distinct 
  yellowish 
  

   shade, 
  as 
  shown 
  in 
  figure 
  6. 
  The 
  yellow, 
  usually 
  somewhat 
  kidney- 
  

   shaped 
  female 
  insects 
  may 
  be 
  found 
  under 
  the 
  scales. 
  A 
  gravid 
  female 
  

   is 
  shown 
  much 
  enlarged 
  in 
  figure 
  10. 
  Note 
  the 
  oval 
  young 
  within 
  her 
  

   body 
  and 
  the 
  slender 
  proboscis 
  apparently 
  composed 
  of 
  two 
  filaments 
  

   but 
  in 
  reality 
  of 
  four. 
  The 
  yellow, 
  active 
  young 
  is 
  shown 
  much 
  enlarged 
  

   in 
  figure 
  11. 
  The 
  antennae, 
  six 
  legs 
  and 
  slender 
  proboscis 
  are 
  all 
  pres- 
  

   ent. 
  The 
  young 
  appear 
  as 
  minute 
  specks 
  when 
  on 
  the 
  trees. 
  They 
  

   soon 
  cover 
  themselves 
  with 
  a 
  white 
  excretion, 
  and 
  then 
  they 
  appear 
  like 
  

   white 
  dots 
  surrounded 
  by 
  red, 
  whenever 
  they 
  estabhsh 
  themselves 
  on 
  

   green 
  fruit 
  or 
  bark 
  (fig. 
  2). 
  The 
  form 
  of 
  the 
  white 
  scale 
  and 
  the 
  colored 
  

   area 
  around 
  it 
  are 
  represented 
  in 
  detail 
  in 
  figure 
  i. 
  

  

  The 
  male 
  scale 
  may 
  be 
  easily 
  recognized 
  by 
  its 
  elongated 
  shape 
  with 
  

   the 
  nipple 
  near 
  one 
  end 
  (fig. 
  8). 
  The 
  delicate, 
  two-winged 
  male 
  is 
  rep- 
  

   resented 
  much 
  enlarged 
  in 
  figure 
  12. 
  

  

  Life 
  history. 
  The 
  winter 
  is 
  passed 
  by 
  this 
  insect 
  in 
  a 
  partly 
  grown, 
  

   dormant 
  condition. 
  Vital 
  activities 
  are 
  resumed 
  with 
  the 
  approach 
  of 
  

   warm 
  weather, 
  and 
  the 
  first 
  outward 
  indications 
  of 
  hfe 
  are 
  seen 
  in 
  the 
  

   appearance 
  of 
  winged 
  males 
  and 
  later 
  of 
  the 
  crawling 
  young, 
  the 
  latter 
  

   of 
  which 
  appear 
  in 
  this 
  latitude 
  toward 
  the 
  last 
  of 
  June. 
  The 
  life 
  his- 
  

   tory 
  of 
  this 
  insect 
  has 
  been 
  studied 
  in 
  detail 
  at 
  Washington 
  (D. 
  C.) 
  

   under 
  the 
  direction 
  of 
  Dr 
  L. 
  O. 
  Howard; 
  and 
  from 
  his 
  account 
  most 
  of 
  

   the 
  following 
  details 
  are 
  taken. 
  The 
  females 
  continue 
  to 
  produce 
  young 
  

   for 
  a 
  period 
  of 
  about 
  six 
  weeks, 
  each 
  averaging 
  about 
  400, 
  or 
  from 
  nine 
  

   to 
  10 
  every 
  24 
  hours. 
  This 
  is 
  an 
  ovoviviparous 
  species. 
  That 
  is 
  the 
  

   eggs 
  develop 
  within 
  the 
  mother 
  and 
  the 
  young 
  are 
  born 
  alive. 
  They 
  

   may 
  be 
  seen 
  as 
  tiny 
  yellow 
  specks 
  escaping 
  from 
  under 
  the 
  maternal 
  

   scale, 
  from 
  which 
  they 
  wander 
  in 
  search 
  of 
  a 
  favorable 
  place 
  to 
  establish 
  

   themselves. 
  This 
  pilgrimage 
  occupies 
  relatively 
  few 
  hours 
  (an 
  average 
  

   of 
  a 
  little 
  over 
  27!- 
  hours, 
  according 
  to 
  Prof. 
  Lowe), 
  and 
  the 
  young 
  

   soon 
  establishes 
  itself, 
  works 
  its 
  slender 
  proboscis 
  through 
  the 
  bark 
  and 
  

   begins 
  to 
  draw 
  noariihin^Q 
  t 
  from 
  the 
  plant. 
  The 
  development 
  of 
  the 
  

  

  