﻿788 
  

  

  REPORT 
  UNITED 
  STATES 
  GEOLOGICAL 
  SURVEY. 
  

  

  Previous 
  to 
  the 
  last 
  molt, 
  however, 
  and 
  before 
  it 
  had 
  gained 
  its 
  full 
  

  

  size, 
  preparatory 
  to 
  

   passing 
  into 
  the 
  adult 
  

   or 
  winged 
  condition, 
  

   the 
  body 
  is 
  covered 
  

   with 
  black 
  tubercles 
  

   from 
  each 
  of 
  whic 
  

   arises 
  a 
  stiff 
  blac 
  

   hair. 
  There 
  is 
  als^ 
  

   a 
  supraaual 
  or 
  dorsal 
  

   black 
  patch 
  on 
  the' 
  

   last 
  segment 
  of 
  the 
  

   body, 
  from 
  which 
  

   arises 
  a 
  pair 
  of 
  black 
  o 
  

   spines. 
  On 
  the 
  back 
  i 
  

   of 
  the 
  false 
  caterpillar 
  i 
  

   the 
  tubercles 
  become 
  i» 
  

   smooth 
  and 
  trans- 
  

   versely 
  oval, 
  and 
  ar- 
  

   ranged 
  in 
  two 
  regular 
  

   rowsi 
  Moreover, 
  a 
  i 
  

   still 
  more 
  important 
  

   characteristic 
  of 
  the 
  

   Fig. 
  58. 
  — 
  Currant 
  saw-fly 
  larva, 
  natural 
  size 
  ; 
  a, 
  enlarged, 
  -^orm 
  in 
  this 
  Stage 
  Is 
  

  

  the 
  jet-black 
  head, 
  which 
  in 
  the 
  fully-grown 
  insect 
  is 
  pale 
  pea-green. 
  

   In 
  Salem, 
  my 
  attention 
  was 
  drawn 
  to 
  the 
  ravages 
  of 
  this 
  worm 
  by 
  Dr. 
  

  

  William 
  Mack^ 
  who 
  found 
  them 
  feeding 
  on 
  the 
  currants 
  in 
  his 
  garden 
  

  

  June 
  8. 
  At 
  this 
  time 
  they 
  were 
  spin- 
  

   ning 
  their 
  cocoons, 
  which 
  were 
  of 
  silk, 
  

   tough, 
  dense, 
  like 
  parchment, 
  and 
  at 
  

   first 
  green, 
  then 
  becoming 
  blackish, 
  and 
  

   covered 
  with 
  i^articles 
  of 
  dirt, 
  and 
  at- 
  

   tached 
  to 
  the 
  leaves 
  in 
  the 
  breeding-box. 
  

   Out 
  of 
  doors 
  they 
  may 
  be 
  found 
  the 
  first 
  

   week 
  in 
  June, 
  and 
  again 
  during 
  the 
  first 
  

   week 
  in 
  July 
  among 
  the 
  leaves 
  and 
  

   stalks 
  on 
  the 
  bushes, 
  or 
  among 
  the 
  

   leaves 
  lying 
  on 
  the 
  ground, 
  or 
  perhaps 
  

   more 
  frequently 
  a 
  little 
  under 
  the 
  sur- 
  

   face 
  of 
  the 
  ground. 
  Here 
  they 
  remain 
  

   between 
  two 
  and 
  three 
  weeks 
  in 
  June, 
  

   the 
  adult 
  flies 
  (in 
  Salem) 
  appearing 
  

   June 
  25. 
  At 
  nearly 
  the 
  same 
  date 
  (June 
  

   29) 
  the 
  worms 
  of 
  the 
  second 
  brood 
  were 
  

   spinning 
  their 
  cocoons. 
  These 
  cocoons 
  

  

  Fig. 
  59.— 
  European 
  Currant 
  SaAT-Fly. 
  (belonging 
  to 
  the 
  secoud 
  brood) 
  remain 
  

   a, 
  male, 
  b, 
  female. 
  (After 
  Riley.) 
  nnder 
  ground 
  or 
  on 
  the 
  leaves 
  about 
  the 
  

  

  roots 
  through 
  the 
  winter, 
  the 
  fl.ies 
  appearing 
  in 
  the 
  spring 
  and 
  laying 
  

  

  their 
  eggs 
  as 
  soon 
  as 
  the 
  leaves 
  unfold. 
  

  

  Not 
  having 
  specimens 
  of 
  both 
  sexes 
  of 
  this 
  saw-fly 
  at 
  hand, 
  I 
  compile 
  

  

  the 
  following 
  description 
  (often 
  using 
  their 
  own 
  words) 
  from 
  Messrs. 
  

  

  Walsh 
  and 
  Riley's 
  account 
  in 
  the 
  American 
  Entomologist, 
  vol. 
  ii, 
  p. 
  16, 
  

  

  from 
  which 
  these 
  illustrations 
  (Fig. 
  59 
  a, 
  &) 
  are 
  taken. 
  

   The 
  female 
  (Fig. 
  59 
  h) 
  is 
  a 
  quarter 
  of 
  an 
  inch 
  long 
  {jW-j-tyo), 
  and 
  is 
  

  

  of 
  a 
  bright 
  honey-yellow 
  color. 
  The 
  head 
  is 
  black, 
  with 
  all 
  the 
  parts 
  

  

  between 
  and 
  below 
  the 
  origin 
  of 
  the 
  anteuuoe, 
  except 
  the 
  tip 
  of 
  the 
  

  

  