﻿HABITS 
  OF 
  THE 
  LAKVA. 
  23 
  

  

  ber 
  of 
  adults 
  were 
  taken 
  from 
  the 
  open 
  on 
  leaves 
  of 
  nasturtium 
  and 
  

   Avere 
  placed 
  in 
  vials. 
  These 
  died 
  in 
  April, 
  giving 
  a 
  length 
  of 
  life 
  

   after 
  being 
  collected 
  of 
  92 
  days. 
  As 
  adults 
  have 
  never 
  been 
  observed 
  

   to 
  emerge 
  from 
  pupae 
  later 
  than 
  December 
  27, 
  these 
  adults 
  must 
  have 
  

   been 
  at 
  least 
  21 
  days 
  old 
  when 
  collected, 
  so 
  that 
  they 
  lived 
  about 
  113 
  

   days. 
  Probably 
  hibernating 
  individuals 
  live 
  as 
  long 
  as 
  5 
  months. 
  

  

  HABITS 
  OF 
  THE 
  LARVA. 
  

  

  In 
  observing 
  the 
  habits 
  of 
  the 
  larva 
  of 
  this 
  thrips, 
  the 
  writer 
  was 
  

   constantly 
  impressed 
  with 
  the 
  great 
  similarity 
  that 
  existed 
  between 
  

   this 
  species 
  and 
  the 
  greenhouse 
  thrips. 
  This 
  is 
  so 
  great 
  that 
  the 
  

   description 
  of 
  habits 
  of 
  the 
  one 
  would 
  almost 
  equally 
  fit 
  the 
  other. 
  

  

  HATCHING. 
  

  

  Apparently 
  the 
  hatching 
  process 
  may 
  occur 
  at 
  any 
  time 
  during 
  

   the 
  day. 
  Many 
  have 
  been 
  observed 
  hatching 
  early 
  in 
  the 
  morning 
  

   and 
  one 
  larva 
  was 
  observed 
  emerging 
  from 
  the 
  egg 
  cavity 
  at 
  4.25 
  

   p. 
  m. 
  Very 
  slowly 
  this 
  larva 
  pushed 
  its 
  way 
  out 
  of 
  the 
  egg 
  cavity, 
  1 
  

   during 
  which 
  time 
  the 
  appendages 
  were 
  all 
  held 
  closely 
  appressed 
  

   to 
  the 
  body 
  and 
  were 
  invisible. 
  As 
  soon 
  as 
  the 
  body 
  was 
  nearly 
  out 
  

   the 
  insect 
  began 
  a 
  slow 
  forward 
  and 
  backward 
  movement 
  and 
  at 
  

   4.40 
  p. 
  m. 
  all 
  but 
  the 
  tip 
  of 
  the 
  abdomen 
  was 
  free, 
  while 
  the 
  larva 
  pro- 
  

   jected 
  straight 
  out 
  from 
  the 
  leaf 
  surface. 
  While 
  held 
  in 
  this 
  position 
  

   it 
  began 
  slowly 
  to 
  unfold 
  the 
  limbs 
  and 
  antennae 
  and 
  move 
  them 
  

   around. 
  The 
  motion 
  was 
  very 
  feeble 
  at 
  first, 
  but 
  gradually 
  the 
  larva 
  

   seemed 
  to 
  gain 
  strength 
  and 
  at 
  4.48 
  p. 
  m. 
  it 
  bent 
  over 
  and, 
  grasping 
  

   the 
  leaf 
  surface, 
  began 
  to 
  pull 
  with 
  its 
  limbs 
  in 
  order 
  to 
  free 
  itself. 
  

   This 
  was 
  accomplished 
  at 
  4.53 
  p. 
  m., 
  making 
  the 
  total 
  period 
  required 
  

   in 
  emerging 
  from 
  the 
  egg 
  28 
  minutes. 
  

  

  The 
  larva? 
  of 
  this 
  insect 
  after 
  hatching 
  move 
  away 
  a 
  short 
  distance, 
  

   then 
  appear 
  to 
  rest 
  for 
  a 
  few 
  minutes 
  until 
  they 
  become 
  stronger. 
  

   Within 
  a 
  short 
  time, 
  however, 
  they 
  move 
  on 
  and 
  soon 
  commence 
  

   feeding. 
  When 
  first 
  hatched 
  the 
  larvae 
  are 
  very 
  minute 
  and 
  almost 
  

   colorless, 
  but 
  as 
  they 
  begin 
  to 
  feed 
  and 
  drain 
  the 
  green 
  coloring 
  

   matter 
  from 
  the 
  leaf 
  the 
  alimentary 
  tract 
  becomes 
  plainly 
  visible 
  

   from 
  the 
  contained 
  food. 
  In 
  a 
  few 
  days 
  the 
  color 
  of 
  the 
  body 
  

   becomes 
  more 
  or 
  less 
  yellowish 
  and 
  blotched 
  with 
  crimson. 
  In 
  com- 
  

   mon 
  with 
  other 
  species 
  of 
  Heliothrips, 
  the 
  larva^ 
  of 
  the 
  present 
  

   species 
  keep 
  the 
  tip 
  of 
  the 
  abdomen 
  elevated 
  and 
  carry 
  around 
  on 
  it 
  

   a 
  small 
  globule 
  of 
  reddish 
  liquid 
  excrement. 
  Gradually 
  this 
  globule 
  

   increases 
  in 
  size 
  until 
  it 
  is 
  too 
  Large 
  to 
  be 
  carried 
  any 
  longer 
  and 
  it 
  

   falls 
  to 
  the 
  leaf 
  surface. 
  Here 
  in 
  time 
  it 
  dries 
  and 
  forms 
  a 
  black 
  

   spot 
  or 
  scale. 
  The 
  occurrence 
  of 
  these 
  spots 
  on 
  the 
  leaf 
  of 
  a 
  plant 
  

  

  1 
  Tins 
  larva 
  emerges 
  from 
  tl 
  -u 
  bj 
  the 
  same 
  method 
  thai 
  Is 
  used 
  by 
  the 
  conchuela 
  

  

  {Pentatoma 
  Ugata 
  Say) 
  as 
  described 
  by 
  Morrill 
  (Bui. 
  86, 
  Bur. 
  Ent., 
  r. 
  s. 
  Dept. 
  Am-., 
  pp. 
  

  

  38 
  ::;•). 
  

  

  