﻿260 
  REPORT 
  UNITED 
  STATES 
  ENTOMOLOGICAL 
  COMMISSION. 
  

  

  feeding 
  on 
  locust 
  eggs 
  has 
  been 
  confirmed 
  by 
  obtaining 
  them 
  from 
  the 
  

   egg-masses 
  of 
  several 
  other 
  species, 
  and 
  the 
  fact 
  that 
  they 
  have 
  a 
  similar 
  

   habit 
  on 
  the 
  Pacific 
  coast 
  is 
  shown 
  by 
  the 
  frequent 
  presence 
  of 
  the 
  

   coarctate 
  larva 
  among 
  the 
  eggs 
  of 
  the 
  destructive 
  locust 
  of 
  California 
  

   (Gamnula 
  pellucida 
  Scudd 
  331 
  ). 
  

  

  One 
  experience 
  with 
  them 
  is 
  worthy 
  of 
  record 
  in 
  this 
  connection, 
  i. 
  e., 
  

   the 
  retarded 
  development 
  that 
  is 
  often 
  manifest 
  in 
  certain 
  individuals, 
  

   as 
  stated 
  in 
  a 
  recent 
  number 
  of 
  the 
  American 
  Entomologist 
  : 
  

  

  "In 
  the 
  month 
  of 
  October, 
  1877, 
  we 
  hatched 
  a 
  number 
  of 
  triungulins 
  

   from 
  the 
  same 
  batch 
  of 
  eggs 
  laid 
  by 
  a 
  female 
  of 
  the 
  Striped 
  Blister- 
  

   beetle 
  (Epicauta 
  vitiata), 
  and 
  fed 
  them 
  on 
  the 
  eggs 
  of 
  the 
  Differential 
  

   Locust 
  ( 
  Caloptenus 
  differ 
  entialis). 
  Several 
  of 
  the 
  resulting 
  beetles 
  issued 
  

   the 
  following 
  summer; 
  three 
  of 
  them 
  passed 
  a 
  second 
  winter 
  in 
  the 
  

   coarctate 
  larva 
  state, 
  and 
  issued 
  as 
  beetles 
  the 
  second 
  summer; 
  while 
  

   one 
  remained 
  unchanged 
  during 
  this 
  second 
  summer 
  of 
  1879. 
  We 
  ex- 
  

   amined 
  it 
  from 
  month 
  to 
  month, 
  always 
  finding 
  it 
  healthy, 
  but 
  began 
  to 
  

   fear, 
  as 
  the 
  present 
  summer 
  approached, 
  that 
  it 
  must 
  have 
  been 
  injured 
  

   and 
  was 
  really 
  dead. 
  It 
  was 
  unchanged 
  on 
  the 
  3d 
  of 
  May 
  of 
  the 
  present 
  

   year, 
  but 
  on 
  looking 
  at 
  it 
  again 
  on 
  the 
  15th 
  of 
  June, 
  we 
  were 
  gratified 
  

   to 
  find 
  that 
  it 
  had 
  left 
  its 
  rigid 
  skin 
  and 
  presented 
  itself 
  in 
  the 
  form 
  of 
  

   the 
  final 
  or 
  third 
  larva. 
  It 
  had 
  transformed 
  to 
  the 
  true 
  pupa 
  on 
  the 
  1st 
  

   of 
  July, 
  and 
  would 
  undoubtedly 
  have 
  given 
  out 
  the 
  beetle 
  two 
  weeks 
  

   later 
  had 
  we 
  not 
  preferred 
  to 
  preserve 
  it 
  in 
  the 
  pupa 
  state 
  for 
  our 
  

   cabinet. 
  

  

  "In 
  this 
  case 
  the 
  individual, 
  though 
  submitted 
  to 
  exactly 
  the 
  same 
  

   conditions 
  as 
  the 
  other 
  specimens, 
  which 
  had 
  simultaneously 
  hatched 
  

   with 
  it 
  — 
  but 
  which 
  went 
  through 
  all 
  their 
  transformations 
  within 
  either 
  

   one 
  or 
  two 
  years 
  — 
  remained 
  dormant 
  for 
  nearly 
  three 
  years, 
  with 
  their 
  

   repeated 
  changes 
  of 
  season 
  and 
  temperature. 
  With 
  the 
  exception 
  of 
  

   the 
  first 
  winter, 
  when 
  it 
  was 
  kept 
  indoors 
  without 
  freezing 
  and 
  when 
  

   development 
  should 
  have 
  been 
  presumably 
  hastened, 
  the 
  specimen 
  was 
  

   kept 
  in 
  a 
  tin 
  box 
  buried 
  the 
  proper 
  distance 
  beneath 
  the 
  ground 
  out 
  of 
  

   doors, 
  so 
  as 
  to 
  be 
  as 
  nearly 
  as 
  possible 
  under 
  natural 
  conditions." 
  

  

  This 
  irregularity 
  in 
  the 
  development 
  of 
  individuals 
  is 
  noticeable 
  in 
  

   many 
  insects 
  that 
  are 
  parasitic 
  and 
  whose 
  mode 
  of 
  life 
  is 
  precarious. 
  

   In 
  the 
  case 
  of 
  our 
  blister-beetles, 
  depending 
  as 
  they 
  do 
  on 
  locust 
  eggs, 
  

   and 
  especially 
  in 
  the 
  case 
  of 
  those 
  which 
  feed 
  particularly 
  on 
  the 
  eggs 
  

   of 
  migratory 
  species, 
  it 
  is 
  not 
  difficult 
  to 
  perceive 
  how 
  this 
  trait 
  may 
  

   prove 
  serviceable 
  to 
  the 
  species 
  possessing 
  it. 
  Migratory 
  locusts 
  occur 
  

   in 
  immense 
  numbers 
  in 
  some 
  particular 
  part 
  of 
  the 
  country 
  at 
  irregu- 
  

   lar 
  intervals, 
  and 
  there 
  are 
  periods 
  or 
  years 
  of 
  absolute 
  immunity 
  from 
  

   their 
  presence 
  in 
  the 
  same 
  regions. 
  The 
  young 
  blister-beetles 
  that 
  hatch 
  

   the 
  year 
  following 
  the 
  advent 
  of 
  the 
  locusts 
  in 
  immense 
  numbers 
  may 
  

   frequently 
  find 
  few 
  or 
  no 
  locust 
  eggs 
  upon 
  which 
  to 
  prey, 
  and 
  the 
  great 
  

   bulk 
  of 
  them 
  would, 
  as 
  a 
  consequence, 
  perish 
  ; 
  while 
  the 
  young 
  from 
  such 
  

  

  * 
  il 
  Q2dij)oda 
  atrox 
  of 
  our 
  First 
  Report. 
  

  

  