﻿446 
  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  apices 
  appearing 
  at 
  the 
  sides 
  of 
  the 
  superiors; 
  female 
  generally 
  without 
  

   thornlike 
  vertical 
  spines. 
  

  

  a) 
  Imago 
  A 
  single 
  cell 
  between 
  veins 
  Ai 
  and 
  A2 
  at 
  their 
  origin 
  ; 
  seg- 
  

   ments 
  8 
  and 
  9 
  of 
  abdomen 
  of 
  about 
  equal 
  length, 
  7-9 
  greatly 
  dilated, 
  in 
  

   width 
  almost 
  equaling 
  the 
  thorax; 
  vulvar 
  lamina 
  of 
  the 
  female 
  about 
  half 
  

   as 
  long 
  as 
  the 
  ninth 
  abdominal 
  segment. 
  Nymph 
  with 
  a 
  broad, 
  obtusely 
  

   pointed 
  abdomen 
  ; 
  lateral 
  spines 
  oa 
  the 
  ninth 
  abdominal 
  segment 
  twice 
  

   as 
  long 
  as 
  the 
  10th 
  segment, 
  the 
  latter 
  segment 
  thus 
  appearing 
  incased 
  

   in 
  the 
  ninth 
  ; 
  median 
  impressed 
  line 
  on 
  abdomen 
  distinct, 
  and 
  no 
  dorsal 
  

   hooks 
  except 
  the 
  merest 
  rudiments 
  on 
  segments 
  8 
  and 
  9. 
  

  

  &) 
  Face 
  of 
  imago 
  lineate 
  with 
  biack. 
  Length 
  of 
  full 
  grown 
  nymph 
  

  

  29mm 
  G. 
  a 
  d 
  e 
  1 
  p 
  h 
  u 
  » 
  

  

  &&) 
  Face 
  of 
  imago 
  entirely 
  yellow. 
  Length 
  of 
  full 
  grown 
  nympJi 
  

  

  33 
  mm 
  G. 
  f 
  r 
  a 
  t 
  e 
  r 
  n 
  u 
  s 
  

  

  aa) 
  Imago 
  Normally 
  two 
  cells 
  between 
  veins 
  Ai 
  and 
  A^^ 
  at 
  their 
  origin 
  ; 
  

   ninth 
  abdominal 
  segment 
  a 
  little 
  longer 
  than 
  eighth; 
  segments 
  7-9 
  

   less 
  dilated; 
  vulvar 
  lamina 
  of 
  female 
  one 
  third 
  to 
  one 
  10th 
  as 
  long 
  as- 
  

   the 
  ninth 
  segment. 
  NympJi 
  with 
  lanceolate, 
  pointed 
  abdomen 
  ; 
  the 
  lateral 
  

   spines 
  on 
  the 
  ninth 
  segment 
  generally 
  shorter 
  than 
  the 
  10th 
  segment 
  and 
  

   not 
  inclosing 
  it; 
  dorsal 
  hooks 
  represented 
  by 
  rudiments 
  of 
  some 
  of 
  the 
  

   segments 
  before 
  the 
  eighth; 
  impressed 
  middorsal 
  line 
  visible 
  only 
  toward 
  

   the 
  bases 
  of 
  the 
  middle 
  segments. 
  

  

  6) 
  Imago 
  Length 
  45 
  mm 
  ; 
  legs 
  all 
  black 
  ; 
  nymph 
  unknown 
  

  

  G. 
  quadricolor 
  

   &&) 
  Imago 
  Length 
  over 
  50 
  mm; 
  fore 
  femora 
  yellow 
  or 
  green 
  below 
  ; 
  

   nympli 
  with 
  very 
  low, 
  obtuse, 
  inconspicuous 
  rudiments 
  of 
  dorsal 
  hooks* 
  

   c) 
  Imago 
  Tibiae 
  black 
  externally; 
  inferior 
  abdominal 
  appendage 
  

   male 
  with 
  an 
  inferior 
  tooth 
  ; 
  vulvar 
  lamina 
  of 
  the 
  female 
  about 
  one 
  

   third 
  the 
  length 
  of 
  the 
  ninth 
  abdominal 
  segment. 
  Nymph 
  with 
  about 
  

   eight 
  to 
  10 
  teeth 
  on 
  the 
  inner 
  margin 
  of 
  the 
  lateral 
  lobe 
  of 
  the 
  labium 
  

  

  G. 
  descriptus 
  

   cc) 
  Imago. 
  Tibiae 
  yellow 
  externally 
  ; 
  superior 
  abdominal 
  append- 
  

   age 
  of 
  the 
  male 
  with 
  an 
  obtuse 
  inferior 
  lobe; 
  vulvar 
  lamina 
  of 
  the 
  

   female 
  about 
  one 
  10th 
  as 
  long 
  as 
  the 
  ninth 
  abdomiual 
  segment. 
  

   Nymph 
  with 
  about 
  six 
  to 
  eight 
  teeth 
  on 
  the 
  inner 
  margin 
  of 
  the 
  

  

  lateral 
  lobe 
  of 
  the 
  labium 
  G. 
  sordidus 
  

  

  blh) 
  Imago 
  Length 
  about 
  48 
  mm 
  ; 
  tibiae 
  yellow 
  externally 
  ; 
  yellow 
  

   on 
  the 
  dorsum 
  of 
  abdominal 
  segments 
  9 
  and 
  10. 
  Nymph 
  with 
  pointed 
  

   rudimentary 
  dorsal 
  hooks 
  on 
  segments 
  6-9 
  G, 
  exilis 
  

  

  Subgenus 
  gomphurus 
  

  

  Imago. 
  A 
  single 
  cell 
  between 
  veins 
  Ai 
  and 
  A2 
  at 
  their 
  origin, 
  hav- 
  

   ing 
  a 
  thickened 
  margin, 
  forming 
  an 
  anal 
  loop; 
  abdominal 
  segments 
  7-9 
  

   greatly 
  dilated, 
  as 
  wide 
  as 
  or 
  wider 
  than 
  the 
  thorax 
  : 
  eighth 
  segment 
  cut 
  

   squarely 
  on 
  apex 
  ; 
  posterior 
  hamule 
  of 
  male 
  perpendicular 
  ; 
  hind 
  femora 
  

   similar 
  in 
  the 
  two 
  sexes. 
  

  

  