﻿220 
  

   Vassiliev 
  (I. 
  v.). 
  lilejiKonpflAbi 
  cocHOBbm 
  v\ 
  KeAP0Bbm,MX-b 
  oSpaai* 
  

  

  HiMSHM, 
  BpeflHafl 
  AtflTenbHOCTb 
  M 
  CnOG06bl 
  6opb6bl 
  Cb 
  HMMM. 
  

  

  [Dendrolimus 
  pini, 
  L., 
  and 
  Dendrolimiis 
  sefjregatuh, 
  But!., 
  their 
  

   ]ife-history, 
  injurious 
  activities 
  and 
  methods 
  of 
  fighting 
  them.] 
  

   Tpyflbi 
  Bwpo 
  no 
  SHTOMonoriw 
  yneHaro 
  KoMMTeia 
  fnaBHaro 
  

  

  VnpaBJieHifl 
  3. 
  M 
  3. 
  [Memoirs 
  of 
  the 
  Bureau 
  of 
  Entomology 
  of 
  the 
  

   Scientific 
  Committee 
  of 
  the 
  Central 
  Board 
  of 
  Land 
  Administration 
  

   and 
  Agriculture,] 
  St. 
  Petersburg, 
  v, 
  no. 
  7, 
  1913, 
  99 
  pp., 
  34 
  figs., 
  

   2 
  col. 
  plates. 
  (Second, 
  enlarged 
  edition). 
  

  

  This 
  is 
  an 
  enlarged 
  edition 
  of 
  the 
  author's 
  report 
  on 
  Dendrolimus 
  

   pini 
  and 
  D. 
  segregatus, 
  after 
  investigating 
  in 
  1898 
  and 
  1899 
  the 
  devas- 
  

   tation 
  caused 
  by 
  the 
  latter 
  in 
  the 
  forests 
  of 
  the 
  government 
  of 
  Irkutsk 
  

   (Siberia). 
  After 
  describing 
  fully 
  all 
  the 
  stages 
  of 
  these 
  two 
  moths, 
  

   the 
  author 
  proceeds 
  to 
  deal 
  with 
  the 
  life-history 
  of 
  D. 
  pini. 
  Hot 
  dry 
  

   weather 
  accelerates 
  the 
  development 
  of 
  the 
  earlier 
  stages 
  and 
  the 
  appear- 
  

   ance 
  of 
  the 
  imago, 
  while 
  a 
  cold, 
  wet 
  summer 
  has 
  an 
  opposite 
  effect. 
  

   In 
  most 
  parts 
  of 
  Russia 
  the 
  moths 
  start 
  flying 
  from 
  the 
  end 
  of 
  June 
  

   to 
  the 
  beginning 
  of 
  July, 
  and 
  attain 
  their 
  maximum 
  during 
  the 
  middle 
  

   of 
  July. 
  A 
  full 
  account 
  is 
  given 
  of 
  the 
  oviposition, 
  development, 
  

   hibernation, 
  pupation, 
  etc., 
  of 
  both 
  D. 
  j)ini 
  and 
  D. 
  segregatus. 
  The 
  

   flying 
  of 
  the 
  latter 
  species 
  in 
  the 
  forests 
  of 
  the 
  southern 
  part 
  of 
  the 
  

   government 
  of 
  Irkutsk 
  took 
  place 
  in 
  1899 
  at 
  the 
  end 
  of 
  June 
  and 
  the 
  

   beginning 
  of 
  July, 
  and 
  after 
  the 
  27th 
  July 
  no 
  live 
  moths 
  were 
  to 
  be 
  

   found, 
  the 
  earth 
  everywhere 
  in 
  the 
  forests 
  being 
  covered 
  by 
  their 
  dead 
  

   bodies. 
  These 
  insects 
  were 
  specially 
  abundant 
  in 
  woods 
  consisting 
  

   of 
  Pinus 
  cembra 
  and 
  in 
  the 
  " 
  taiga,"* 
  while 
  they 
  were 
  totally 
  absent 
  

   in 
  pure 
  birch-woods 
  and 
  in 
  mixed 
  woods 
  of 
  pine, 
  larch 
  and 
  birch 
  trees 
  ; 
  

   in 
  pure 
  pine 
  woods 
  they 
  were 
  found 
  only 
  where 
  the 
  latter 
  joined 
  the 
  

   affected 
  areas. 
  In 
  1898 
  there 
  were 
  very 
  few 
  moths 
  in 
  the 
  forests 
  of 
  

   the 
  government 
  and 
  the 
  author 
  did 
  not 
  find 
  any 
  of 
  their 
  eggs, 
  but 
  

   there 
  were 
  plenty 
  of 
  caterpillars 
  ; 
  this 
  fact 
  led 
  him 
  to 
  assume 
  that 
  the 
  

   development 
  of 
  the 
  insect 
  takes 
  two 
  years, 
  that 
  the 
  year 
  1898 
  

   was 
  not 
  a 
  " 
  flying 
  " 
  year, 
  and 
  that 
  the 
  year 
  1899 
  would 
  

   witness 
  an 
  outbreak 
  of 
  the 
  moths 
  and 
  extensive 
  oviposition. 
  This 
  

   assumption 
  proved 
  quite 
  correct 
  and 
  early 
  in 
  July 
  1899 
  there 
  was 
  

   scarcely 
  a 
  small 
  plant 
  which 
  did 
  not 
  bear 
  eggs 
  of 
  D. 
  segregatus. 
  The 
  

   trees 
  most 
  affected 
  were 
  Pinus 
  cembra, 
  the 
  silver 
  fir 
  (Abies 
  pectinata) 
  

   and 
  the 
  spruce 
  (Picea 
  excelsa) 
  ; 
  less 
  frequently 
  the 
  eggs 
  were 
  found 
  on 
  

   needles 
  of 
  pines 
  and 
  larches, 
  while 
  in 
  exceptional 
  cases 
  only 
  were 
  they 
  

   found 
  on 
  leaves 
  of 
  birch, 
  aspen, 
  service 
  trees, 
  spiraea, 
  red 
  and 
  black 
  

   bilberry 
  and 
  various 
  grasses. 
  It 
  was 
  observed 
  that 
  the 
  insects 
  did 
  not 
  

   oviposit 
  on 
  plants 
  affording 
  a 
  limited 
  supply 
  of 
  food 
  ; 
  eggs 
  were 
  seldom 
  

   found 
  on 
  freshly 
  stripped 
  or 
  withered 
  plants, 
  in 
  w^hich 
  respect 
  this 
  species 
  

   differs 
  from 
  D. 
  pini, 
  the 
  females 
  of 
  which 
  oviposit 
  indiscriminately 
  

   on 
  plants 
  in 
  any 
  state. 
  Most 
  of 
  the 
  eggs 
  were 
  laid 
  on 
  the 
  needles 
  and 
  

   only 
  in 
  a 
  few 
  exceptional 
  cases 
  were 
  they 
  found 
  on 
  the 
  branches 
  or 
  

   trunks. 
  The 
  total 
  number 
  of 
  eggs 
  deposited 
  by 
  one 
  female 
  is 
  on 
  the 
  

   average 
  about 
  200, 
  the 
  maximum 
  number 
  being 
  315. 
  The 
  hatching 
  

   of 
  the 
  caterpillars 
  proceeded 
  from 
  the 
  middle 
  of 
  July 
  till 
  the 
  middle 
  

  

  * 
  [•' 
  Taiga 
  " 
  is 
  a 
  Siberian 
  word 
  signifiying 
  a 
  dense, 
  more 
  or 
  less 
  impenetrable 
  

   forest, 
  often 
  of 
  a 
  swampy 
  character. 
  — 
  Ed.] 
  

  

  