﻿21 
  

  

  August 
  the 
  second 
  brood 
  of 
  larv?e 
  has 
  been 
  observed, 
  and 
  beetles, 
  

   apparently 
  just 
  issued, 
  were 
  found 
  in 
  September. 
  The 
  larvte 
  feed 
  

   preferably 
  upon 
  active 
  young 
  or 
  recently 
  set 
  scales, 
  and 
  where 
  they 
  

   are 
  at 
  all 
  numerous 
  undoubtedly 
  destroy 
  a 
  great 
  number. 
  When 
  

   full 
  grown, 
  the 
  beetle 
  larva 
  attaches 
  itself 
  to 
  the 
  bark 
  by 
  the 
  anal 
  

   extremity, 
  suspends 
  itself 
  head 
  down, 
  the 
  skin 
  splits, 
  and 
  the 
  pupa 
  

   wriggles 
  partially 
  out 
  of 
  it. 
  In 
  this 
  condition 
  it 
  remains 
  for 
  a 
  few 
  

   days, 
  until 
  ready 
  to 
  transform 
  to 
  an 
  adult. 
  This 
  beetle 
  I 
  believe 
  to 
  

   be 
  the 
  most 
  effective 
  enemy 
  of 
  the 
  San 
  Jose 
  scale 
  in 
  California. 
  

   Combined 
  with 
  Aphelinus, 
  it 
  has 
  done 
  most 
  effective 
  work 
  in 
  the 
  

   southern 
  counties, 
  and 
  is. 
  I 
  believe, 
  largely 
  responsible 
  for 
  the 
  de- 
  

   crease 
  of 
  the 
  scale 
  in 
  that 
  part 
  of 
  the 
  country."* 
  

  

  The 
  third 
  of 
  the 
  notably 
  helpful 
  species 
  {Smilid 
  niisella) 
  is 
  a 
  very 
  

   minute 
  ladybird, 
  smaller 
  than 
  the 
  San 
  Jose 
  scale 
  itself, 
  shining 
  black 
  

   and 
  broadly 
  oval 
  in 
  outline. 
  It 
  was 
  abundant 
  in 
  September 
  in 
  the 
  

   Quincy 
  orchard, 
  in 
  this 
  State, 
  feeding 
  freely 
  upon 
  the 
  San 
  Jose 
  scale 
  

   there 
  and 
  breeding 
  actively. 
  It 
  is 
  comiDaratively 
  little 
  known 
  in 
  

   California, 
  where 
  it 
  has, 
  indeed, 
  only 
  recently 
  been 
  ascertained 
  to 
  

   occur 
  as 
  a 
  native 
  insect. 
  It 
  is 
  apparently 
  the 
  most 
  active 
  enemy 
  of 
  

   the 
  San 
  Jose 
  scale 
  in 
  our 
  region, 
  and 
  must. 
  I 
  think, 
  produce 
  a 
  

   marked 
  effect 
  upon 
  the 
  rate 
  of 
  multiplication 
  of 
  that 
  species. 
  Its 
  life 
  

   history, 
  as 
  given 
  by 
  Professor 
  Smith, 
  is 
  highly 
  favorable 
  to 
  this 
  sup- 
  

   position, 
  for 
  it 
  seems 
  to 
  breed 
  here 
  as 
  early 
  and 
  almost 
  as 
  long 
  as 
  the 
  

   scale 
  itself, 
  and 
  has 
  been 
  found 
  abundant 
  in 
  November 
  and 
  Decem- 
  

   ber. 
  The 
  beetles 
  are 
  said 
  to 
  i^refer 
  the 
  full-grown 
  female 
  scales, 
  but 
  

   the 
  larvjTp 
  feed 
  actively 
  on 
  the 
  younger 
  individuals. 
  We 
  found 
  this 
  

   beetle 
  abundant 
  at 
  Champaign 
  April 
  10, 
  1889. 
  on 
  pine-trees 
  heavily 
  

   infested 
  with 
  the 
  pine-leaf 
  scale 
  [Chionasjiis 
  pin 
  if 
  olid'.) 
  A 
  dissec- 
  

   tion 
  of 
  specimens 
  collected 
  at 
  the 
  time 
  showed 
  that 
  they 
  were 
  feed- 
  

   ing 
  upon 
  the 
  scales. 
  f 
  

  

  Efficient 
  as 
  these 
  insect 
  enemies 
  may 
  prove 
  to 
  be 
  as 
  a 
  means 
  of 
  

   checking 
  the 
  multiplication 
  of 
  the 
  scale 
  when 
  left 
  to 
  itself, 
  they 
  have 
  

   the 
  disadvantage 
  as 
  an 
  economic 
  reliance 
  that 
  artificial 
  measures 
  for 
  

   the 
  destruction 
  of 
  the 
  scale 
  must 
  destroy 
  these 
  parasitic 
  and 
  preda- 
  

   ceous 
  enemies 
  also. 
  Indeed, 
  the 
  fact 
  is 
  now 
  well 
  recognized 
  that 
  the 
  

   economic 
  uses 
  of 
  parasites 
  and 
  insecticides 
  are 
  usually 
  antagonistic, 
  

   and 
  unless 
  we 
  are 
  obliged 
  to 
  al)andon 
  the 
  effort 
  to 
  exterminate 
  the 
  scale 
  

   in 
  Illinois, 
  we 
  can 
  pay 
  but 
  little 
  attention 
  to 
  the 
  introduction 
  and 
  arti- 
  

   ficial 
  multiplication 
  of 
  these 
  entomological 
  enemies 
  of 
  the 
  species, 
  

   which 
  can 
  never 
  be 
  expected 
  to 
  exterminate 
  any 
  insect, 
  but 
  can 
  at 
  

   best 
  only 
  reduce 
  its 
  average 
  numbers 
  to 
  economic 
  insignificance. 
  In 
  

   fact, 
  in 
  those 
  parts 
  of 
  California 
  the 
  climate 
  of 
  which 
  most 
  nearly 
  

  

  * 
  Prof. 
  Smith's 
  Report, 
  pp. 
  521, 
  522. 
  

  

  t 
  It 
  is 
  a 
  source 
  of 
  frequent 
  surprise 
  to 
  me 
  that 
  the 
  dissection 
  method 
  of 
  determiniuy:the 
  

   food 
  of 
  insects 
  is 
  almost 
  never 
  resorted 
  to 
  by 
  economic 
  entomologists 
  in 
  this 
  country, 
  not- 
  

   withstanding 
  the 
  abundant 
  evidence 
  which 
  has 
  been 
  given 
  of 
  its 
  usefulness 
  in 
  settling 
  

   points 
  left 
  doubtful 
  by 
  observation, 
  and 
  even 
  in 
  discoverins 
  food 
  habits 
  not 
  previously 
  sus- 
  

   pected. 
  (See 
  'Notes 
  on 
  Insectivorous 
  Coleoptera." 
  and 
  "The 
  Food 
  Relations 
  of 
  the 
  Cara- 
  

   bidif 
  and 
  Coccinellidie." 
  Bull. 
  111. 
  State 
  Lab. 
  Nat. 
  Hist.. 
  Vol. 
  I., 
  Art. 
  3., 
  pp. 
  153-158. 
  and 
  Art. 
  6, 
  

   pp. 
  33-59). 
  Even 
  pinned 
  insects 
  which 
  have 
  been 
  dried 
  for 
  years 
  may 
  be 
  readily 
  dissected 
  

   after 
  boiling 
  for 
  a 
  little 
  time 
  in 
  dilute 
  potash 
  solution, 
  and 
  will 
  then 
  disclose 
  the 
  nature 
  of 
  

   the 
  last 
  food 
  taken 
  on 
  an 
  examination 
  of 
  the 
  contents 
  of 
  the 
  aliiiuintary 
  canal 
  displayed 
  

   upon 
  a 
  slide 
  in 
  glycerine 
  under 
  a 
  compound 
  microscope. 
  

  

  