﻿— 
  79 
  — 
  

  

  •"rising 
  in 
  clouds," 
  nine 
  tenths 
  of 
  them 
  nymphs. 
  None 
  of 
  the 
  imagos 
  

   are 
  recorded 
  in 
  Illinois 
  from 
  November 
  ist 
  to 
  the 
  last 
  of 
  April, 
  and 
  it 
  is 
  

   almost 
  certain 
  that 
  they 
  pass 
  the 
  winter 
  in 
  the 
  egg. 
  It 
  can 
  only 
  be 
  

   surmised 
  from 
  present 
  data 
  that 
  there 
  are 
  four 
  or 
  more 
  broods 
  in 
  a 
  

   season 
  in 
  central 
  Illinois. 
  

  

  Empoasca 
  flavescens 
  Fabr. 
  

   (PI. 
  II., 
  Fig. 
  4.) 
  

  

  This 
  is 
  closely 
  related 
  to 
  the 
  preceding 
  species 
  and 
  similar 
  to 
  it 
  in 
  

   habit 
  and 
  food 
  plants, 
  so 
  far 
  as 
  these 
  are 
  known 
  to 
  us. 
  It 
  was 
  not 
  

   found 
  among 
  the 
  sugar-beet 
  leaf-hoppers 
  until 
  fall, 
  but 
  became 
  very 
  

   common 
  in 
  October, 
  more 
  so 
  indeed 
  than 
  inali. 
  It 
  is 
  whiter 
  than 
  niali, 
  

   and 
  has 
  only 
  three 
  spots 
  on 
  the 
  margin 
  of 
  the 
  thorax. 
  These 
  are 
  not 
  

   always 
  distinct, 
  and 
  indefinite 
  markings 
  resembling 
  them 
  may 
  be 
  noted 
  

   in 
  some 
  similarly 
  colored 
  species 
  of 
  related 
  genera, 
  which 
  may 
  be 
  

   distinguished 
  by 
  their 
  venation, 
  as 
  mentioned 
  above. 
  The 
  species 
  is 
  

   common 
  and 
  widespread, 
  and 
  is 
  reported 
  from 
  localities 
  ranging 
  from 
  

   New 
  York 
  and 
  the 
  District 
  of 
  Columbia 
  to 
  California 
  and 
  Mexico. 
  Its 
  

   smoky-winged 
  variety, 
  birdii, 
  is 
  recorded 
  from 
  New 
  York, 
  Michigan, 
  

   Illinois, 
  and 
  Iowa, 
  on 
  apple, 
  hops, 
  walnut, 
  beans, 
  and 
  weeds. 
  

  

  It 
  has 
  been 
  collected 
  December 
  i6th, 
  and 
  again 
  among 
  leaves 
  in 
  the 
  

   woods 
  in 
  early 
  spring. 
  We 
  have 
  taken 
  it 
  as 
  early 
  as 
  April 
  20th. 
  This 
  

   indicates 
  hibernation 
  as 
  an 
  imago, 
  and 
  considering 
  its 
  abundance 
  in 
  late 
  

   fall 
  it 
  is 
  evident 
  that 
  its 
  life 
  history 
  is 
  unlike 
  that 
  of 
  mali 
  — 
  perhaps 
  more 
  

   like 
  that 
  of 
  the 
  Typhlocybas 
  next 
  to 
  be 
  treated. 
  

  

  The 
  Grape 
  Leaf-hoppers. 
  

  

  Typhlocyba. 
  

  

  (PI. 
  III., 
  Fig. 
  I.) 
  

  

  Early 
  in 
  October, 
  on 
  sugar 
  beets 
  on 
  the 
  University 
  farm, 
  the 
  species 
  

   Typhlocyba 
  vidnerata 
  Fitch 
  was 
  very 
  common, 
  and 
  a 
  few 
  of 
  T. 
  comes 
  

   Say 
  and 
  its 
  variety 
  vitis 
  Harr. 
  were 
  also 
  seen. 
  These 
  and 
  a 
  number 
  of 
  

   other 
  tiny 
  leaf-hoppers 
  finely 
  marked 
  in 
  various 
  patterns 
  with 
  scar- 
  

   let, 
  orange, 
  ivory-white, 
  etc., 
  on 
  a 
  pale 
  yellowish 
  white 
  ground 
  color, 
  

   are 
  commonest 
  and 
  very 
  injurious 
  on 
  wild 
  and 
  cultivated 
  grape-vines, 
  

   Virginia 
  creepers 
  and 
  redbud, 
  and 
  also 
  occur 
  on 
  raspberry 
  and 
  a 
  few 
  

   other 
  plants. 
  They 
  are 
  widely 
  distributed 
  throughout 
  the 
  country. 
  

  

  These 
  leaf-hoppers 
  spend 
  the 
  winter 
  as 
  adults 
  in 
  large 
  numbers 
  

   among 
  dead 
  leaves 
  and 
  other 
  trash 
  upon 
  the 
  ground, 
  coming 
  out 
  and 
  

   laying 
  their 
  eggs 
  on 
  the 
  vine 
  leaves 
  when 
  warmer 
  weather 
  comes 
  in 
  

   April 
  and 
  May. 
  By 
  the 
  middle 
  of 
  June 
  the 
  adults 
  become 
  numerous, 
  

   and 
  continue 
  in 
  increasing 
  numbers 
  until 
  the 
  leaves 
  fall 
  at 
  the 
  end 
  of 
  

   the 
  season. 
  All 
  stages 
  may 
  be 
  found 
  on 
  the 
  vines 
  at 
  once, 
  and 
  the 
  suc- 
  

   cession 
  and 
  number 
  of 
  broods 
  has 
  never 
  been 
  made 
  out. 
  

  

  