﻿:S08 
  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  /Male 
  with 
  no 
  ventral 
  hooks 
  on 
  the 
  first 
  abdominal 
  segment; 
  

   female 
  with 
  the 
  hind 
  tibia 
  a 
  little 
  longer 
  than 
  the 
  hind 
  femur 
  ; 
  

  

  the 
  sexes 
  alike 
  in 
  wing 
  pattern 
  Libellula 
  p. 
  530 
  

  

  ff 
  Male 
  with 
  a 
  pair 
  of 
  ventral 
  hooks 
  on 
  the 
  first 
  abdominal 
  segment 
  ; 
  

   female 
  with 
  the 
  hind 
  femur 
  and 
  tibia 
  of 
  equal 
  length 
  j 
  wings 
  

  

  dissimilarly 
  colored 
  in 
  the 
  two 
  sexes 
  Plathemis 
  p. 
  536 
  

  

  -GO 
  Triangle 
  of 
  the 
  fore 
  wing 
  placed 
  beyond 
  the 
  level 
  of 
  the 
  apex 
  of 
  the 
  

  

  triangle 
  of 
  the 
  hind 
  wing 
  ; 
  stigma 
  with 
  its 
  inner 
  end 
  perpendicular, 
  its 
  

  

  outer 
  end 
  very 
  oblique 
  to 
  the 
  bordering 
  veins; 
  wiogs 
  broad 
  at 
  base 
  

  

  and 
  pointed 
  at 
  apex 
  

  

  d 
  Radial 
  sector 
  regularly 
  curved; 
  hind 
  wings 
  with 
  a 
  broad, 
  basal 
  colored 
  

  

  band 
  Tramea 
  p. 
  537 
  

  

  dd 
  Radial 
  sector 
  distinctly 
  undulate; 
  hind 
  wings 
  not 
  covered 
  at 
  base 
  by 
  

   a 
  broad 
  colored 
  band 
  Fantala 
  p. 
  539 
  

  

  Nymphs 
  

  

  a 
  Unknown... 
  Nannothemisi 
  and 
  Micrathyria 
  

  

  na 
  With 
  large, 
  cultriform 
  dorsal 
  hooks 
  on 
  abdominal 
  segments 
  3-9 
  ; 
  eyes 
  small 
  

   and 
  situated 
  on 
  the 
  midlateral 
  margin 
  of 
  the 
  head 
  and 
  directed 
  laterally 
  

  

  Perithemis 
  

  

  -aaa 
  With 
  no 
  dorsal 
  hook 
  on 
  the 
  ninth 
  abdominal 
  segment; 
  eyes 
  overspreading 
  

  

  more 
  or 
  less 
  the 
  anterolateral 
  margins 
  of 
  the 
  head 
  

  

  & 
  Basal 
  segment 
  of 
  the 
  hind 
  tarsus 
  more 
  than 
  half 
  as 
  long 
  as 
  the 
  second 
  

  

  segment; 
  lateral 
  appendages 
  of 
  the 
  abdomen 
  not 
  more 
  than 
  half 
  as 
  long 
  

  

  as 
  the 
  inferiors 
  (except 
  in 
  Libellula 
  quadrimaculata); 
  superior 
  

  

  abdominal 
  appendage 
  regularly 
  tapering 
  to 
  a 
  point 
  

  

  c 
  Abdominal 
  appendages 
  strongly 
  decurved; 
  lateral 
  spines 
  wanting 
  or 
  

  

  extremely 
  rudimentary 
  Mesothemis 
  

  

  CG 
  Abdominal 
  appendages 
  straight 
  or 
  very 
  slightly 
  declined; 
  lateral 
  spines 
  

   evident 
  on 
  abdominal 
  segments 
  8 
  and 
  9 
  

   ^^With 
  no 
  dorsal 
  hooks 
  at 
  all 
  ; 
  abdomen 
  smooth, 
  depressed 
  ; 
  head 
  twice 
  as 
  

   wide 
  as 
  long, 
  with 
  eyes 
  very 
  prominent 
  laterally.. 
  Pachydiplax 
  

   dd 
  Dorsal 
  hooks 
  present, 
  at 
  least 
  on 
  the 
  middle 
  abdominal 
  segments 
  

  

  e 
  Abdomen 
  ovate 
  in 
  outline, 
  rather 
  abruptly 
  narrowed 
  to 
  the 
  posterior 
  

   end; 
  hind 
  margin 
  of 
  the 
  eyes 
  behind 
  the 
  middle 
  of 
  the 
  head 
  

   / 
  Lateral 
  spines 
  long 
  and 
  straight 
  ; 
  abdomen 
  not 
  narrowed 
  posteriorly 
  

  

  before 
  the 
  eighth 
  segment 
  Celithemis 
  

  

  ff 
  Lateral 
  spines 
  shorter 
  and 
  more 
  or 
  less 
  incurvate 
  ; 
  the 
  abdomen 
  

   more 
  or 
  less 
  narrowed 
  before 
  the 
  eighth 
  segment 
  

   g 
  Dorsal 
  hooks 
  as 
  long 
  as 
  the 
  segments 
  which 
  bear 
  them 
  

  

  Leucorhin 
  ia 
  

   gg 
  Dorsal 
  hooks 
  shorter 
  than 
  the 
  segments 
  which 
  bear 
  them 
  

  

  Sympe 
  trum 
  

  

  ee 
  Abdomen 
  lanceolate 
  in 
  outline, 
  slowlv 
  narrowed 
  to 
  the 
  pointed 
  

  

  posterior 
  end 
  ; 
  eyes 
  capping 
  the 
  prominent 
  anterolateral 
  angles 
  of 
  

  

  the 
  head, 
  their 
  hind 
  margin 
  generally 
  before 
  the 
  middle 
  of 
  the 
  top 
  

  

  of 
  the 
  head; 
  body 
  generally 
  hairy 
  

  

  1 
  Discovered 
  since 
  this 
  key 
  was 
  prepared, 
  and 
  described 
  below 
  under 
  the 
  account 
  of 
  the 
  genus. 
  

  

  