﻿AQUATIC 
  INSECTS 
  IN 
  THE 
  ADIRONDACKS 
  

  

  537 
  

  

  1867 
  Libellula 
  trimaculata 
  Packard, 
  Am. 
  nat. 
  1 
  : 
  310, 
  pi. 
  9, 
  fig. 
  1 
  

   1861 
  PI 
  a 
  til 
  em 
  is 
  triraaoulata 
  Hagen, 
  Synopsis 
  Neur. 
  N. 
  Am. 
  p. 
  149 
  

   1873 
  Libellula 
  trimaculata 
  Riley, 
  Ins. 
  Mo. 
  5tli 
  rep't, 
  p. 
  14 
  (This 
  article 
  

   contains 
  a 
  woodcut 
  of 
  this 
  species 
  which 
  has 
  been 
  most 
  extensively 
  

   copied 
  in 
  this 
  country.) 
  

   1893 
  Plat 
  h 
  amis 
  trimaculata 
  Calvert, 
  Am. 
  ent. 
  soc. 
  Trans. 
  20:259 
  

   1895-97 
  Plat 
  hem 
  is 
  trimaculata 
  Calvert, 
  N. 
  Y. 
  ent. 
  soc. 
  Jour. 
  3 
  ; 
  47 
  

   and 
  5: 
  94 
  (listed 
  from 
  New 
  York, 
  Dobbs 
  Ferry, 
  Ithaca, 
  Schoharie, 
  

   Albany 
  and 
  Buffalo) 
  

  

  1898 
  Li 
  bell 
  ul 
  a 
  trimaculata 
  Needham, 
  Outdoor 
  studies, 
  p. 
  57 
  and 
  65, 
  

  

  fig. 
  56 
  and 
  66 
  

  

  1899 
  Plathemis 
  trimaculata 
  Kellicott, 
  Odon. 
  Ohio, 
  p. 
  102 
  (description) 
  

  

  1900 
  Plathemis 
  lydia 
  Williamson, 
  Dragon 
  flies 
  Ind. 
  p. 
  333 
  (description) 
  

   This 
  is 
  another 
  well 
  known, 
  widely 
  distributed 
  and 
  generally 
  common 
  

  

  species, 
  which 
  inhabits 
  ponds 
  and 
  ditches 
  generally. 
  I 
  present 
  herewith 
  

   (fig. 
  32) 
  a 
  figure 
  of 
  its 
  nymph, 
  which 
  I 
  have 
  pre- 
  

   viously 
  published 
  in 
  Outdoor 
  studies. 
  It 
  differs 
  from 
  

   Libellula 
  and 
  Ladona 
  in 
  having 
  the 
  head 
  

   widest 
  behind 
  the 
  eyes, 
  and 
  from 
  Libellula 
  in 
  

   having 
  the 
  front 
  margin 
  of 
  the 
  median 
  lobe 
  of 
  the 
  

   labium 
  crenulate. 
  

  

  Nymph. 
  Total 
  length 
  24 
  mm 
  ; 
  abdomen 
  14 
  mm 
  ; 
  

   hind 
  femur 
  4.5 
  mm; 
  width 
  of 
  head 
  4.5 
  mm, 
  of 
  abdo- 
  

   men 
  5.5 
  mm. 
  

  

  Body 
  elongate, 
  rather 
  smooth, 
  and 
  more 
  free 
  from 
  

   dirt 
  than 
  most 
  Libellulas, 
  generally 
  showing 
  two 
  

   bands 
  of 
  blackish 
  brown 
  extending 
  from 
  beneath 
  the 
  

   tips 
  of 
  the 
  wing 
  cases 
  to 
  the 
  bases 
  of 
  the 
  lateral 
  ap- 
  

   pendages. 
  Head 
  not 
  widened 
  behind 
  the 
  eyes, 
  but 
  

  

  ^.^, 
  °. 
  J 
  1, 
  , 
  J. 
  , 
  , 
  c 
  ^ 
  ^^^ 
  • 
  Fig. 
  33 
  Dorsal 
  view 
  of 
  

  

  With 
  Sides 
  parallel; 
  median 
  lobe 
  of 
  labium 
  promi- 
  nympii 
  of 
  piathemis 
  

   nent, 
  but 
  with 
  no 
  middle 
  tooth 
  on 
  its 
  fore 
  margin 
  ; 
  ^^^^^ 
  ^'*"- 
  

   lateral 
  setae 
  10; 
  mental 
  setae 
  eight; 
  of 
  which 
  the 
  five 
  outer 
  ones 
  are 
  

   longer; 
  abdomen 
  triquetral, 
  with 
  moderate 
  lateral 
  spines 
  on 
  segments 
  

   8 
  and 
  9, 
  and 
  with 
  rudimentary 
  dorsal 
  hooks 
  on 
  segments 
  3-5, 
  highest 
  on 
  

   the 
  fourth 
  segment, 
  absent 
  from 
  the 
  hinder 
  segments; 
  lateral 
  appendages 
  

   about 
  half 
  as 
  long 
  as 
  the 
  equal 
  superior 
  and 
  inferiors. 
  

  

  TRAMEA 
  

  

  But 
  two 
  species 
  of 
  this 
  large 
  genus 
  seem 
  to 
  belong 
  to 
  the 
  New 
  York 
  

   fauna. 
  These 
  are 
  insects 
  of 
  superb 
  aerial 
  powers, 
  representing, 
  together 
  

   with 
  the 
  next 
  genus, 
  the 
  extreme 
  of 
  specialization 
  in 
  wing 
  development, 
  

   at 
  least 
  for 
  the 
  subfamily. 
  Our 
  two 
  species 
  may 
  be 
  recognized, 
  even 
  

   while 
  in 
  flight, 
  by 
  the 
  broad, 
  basal 
  colored 
  band 
  on 
  the 
  hind 
  wings. 
  The 
  

   nymphs 
  agree 
  in 
  having 
  the 
  body 
  smooth, 
  depressed, 
  unusually 
  clean 
  and 
  

   marked 
  with 
  a 
  pattern 
  of 
  brownish 
  on 
  a 
  ground 
  of 
  clear 
  transparent 
  green; 
  

  

  