﻿J 
  AQUATIC 
  INSECTS 
  IN 
  THE 
  ADIRONDACKS 
  535 
  

  

  This 
  species 
  occurred 
  sparingly 
  at 
  Saranac 
  Inn. 
  A 
  few 
  images 
  were 
  

   seen 
  sitting 
  on 
  twigs 
  which 
  rose 
  directly 
  a 
  few 
  feet 
  out 
  of 
  the 
  water. 
  

   They 
  were 
  shy 
  and 
  difficult 
  to 
  capture, 
  and, 
  when 
  disturbed, 
  would 
  rarely 
  

   return 
  to 
  the 
  same 
  vicinity. 
  I 
  have 
  not 
  been 
  able 
  to 
  find 
  this 
  so 
  common 
  

   species 
  in 
  its 
  immature 
  stages 
  in 
  person, 
  but 
  I 
  have 
  nymphs 
  sent 
  me 
  from 
  

   Ellenville 
  N. 
  Y, 
  by 
  Chester 
  Young, 
  and 
  others 
  from 
  the 
  state 
  of 
  Wash- 
  

   ington; 
  these 
  agree 
  well 
  with 
  specimens 
  from 
  France 
  which 
  I 
  have 
  

   received 
  from 
  my 
  esteemed 
  correspondent, 
  M. 
  Rene 
  Martin, 
  of 
  Leblanc. 
  

   The 
  nymph 
  of 
  this 
  species 
  has 
  long 
  been 
  known 
  in 
  Europe. 
  

  

  Nymph. 
  The 
  largest 
  Ellenville 
  nymph, 
  apparently 
  full 
  grown, 
  meas- 
  

   ures 
  in 
  total 
  length 
  26 
  mm; 
  abdomen 
  18 
  mm; 
  hind 
  femur 
  6 
  mm 
  ; 
  width 
  

   of 
  head 
  6 
  mm, 
  of 
  abdomen 
  8 
  mm. 
  

  

  The 
  head 
  is 
  very 
  compact 
  in 
  this 
  nymph, 
  scarcely 
  narrowed 
  behind 
  

   the 
  eyes 
  ; 
  the 
  median 
  lobe 
  of 
  the 
  labium 
  is 
  produced 
  at 
  the 
  middle 
  of 
  its 
  

   free 
  border 
  into 
  a 
  flat, 
  toothlike 
  prominence 
  ; 
  lateral 
  setae 
  seven 
  ; 
  mental 
  

   setae 
  about 
  13, 
  of 
  which 
  the 
  seven 
  outermost 
  are 
  longest; 
  movable 
  

   hook 
  slender 
  and 
  incurvate 
  ; 
  the 
  dorsum 
  of 
  the 
  body 
  is 
  scurfy 
  hairy 
  (hardly 
  

   less 
  so 
  than 
  in 
  L. 
  p 
  u 
  1 
  c 
  h 
  e 
  1 
  1 
  a 
  , 
  described 
  below), 
  and 
  the 
  hairs 
  partly 
  

   obscure 
  the 
  dorsal 
  hooks 
  which 
  are 
  present 
  on 
  segments 
  ^-8 
  of 
  abdomen, 
  

   that 
  of 
  the 
  eighth 
  segment 
  short 
  and 
  rudimentary 
  ; 
  lateral 
  spines 
  very 
  

   short; 
  segment 
  10 
  about 
  half 
  as 
  long 
  on 
  the 
  dorsal 
  as 
  on 
  the 
  ventral 
  

   side 
  ; 
  appendages 
  fully 
  as 
  long 
  as 
  the 
  last 
  two 
  abdominal 
  segments. 
  

   The 
  laterals 
  have 
  unusual 
  length 
  for 
  a 
  member 
  of 
  this 
  genus 
  in 
  being 
  

   but 
  about 
  one 
  fourth 
  shorter 
  than 
  the 
  others. 
  

  

  Libellula 
  semifasciata 
  Burmeister 
  

  

  Plate 
  23, 
  fig. 
  1 
  

   1839 
  Libellula 
  semifasciata 
  Burmeister, 
  Handb. 
  ent. 
  2 
  ; 
  862 
  

   1861 
  Lib 
  ellula 
  semifasciata 
  Hagen, 
  Synopsis 
  Neur. 
  N. 
  Am. 
  p. 
  151 
  

   1839 
  Libellula 
  tern 
  aria 
  Say, 
  Acad. 
  nat. 
  sci. 
  Phil. 
  Jour. 
  8: 
  21 
  

   1842 
  Libellula 
  maculata 
  Rambur, 
  Ins. 
  Neur. 
  p. 
  55 
  

   1893 
  Libellula 
  semifasciata 
  Cal 
  vert, 
  Am. 
  ent. 
  soc. 
  Trans. 
  20 
  : 
  258 
  

   1895-97 
  Libellula 
  semifasciata 
  Calvert, 
  N. 
  Y. 
  ent. 
  soc. 
  Jour. 
  3 
  : 
  47 
  and 
  

   5 
  : 
  94 
  (listed 
  from 
  New 
  York, 
  Dobbs 
  Ferry 
  and 
  Buffalo) 
  

  

  1898 
  Lib 
  ellula 
  semifasciata 
  Needham, 
  Outdoor 
  studies, 
  p. 
  55, 
  fig. 
  54 
  

  

  1899 
  Libellula 
  semifasciata 
  Kellicott, 
  Odon. 
  Ohio, 
  p. 
  100 
  (description) 
  

  

  1900 
  Libellula 
  semifasciata 
  Williamson, 
  Dragon 
  flies 
  Ind. 
  p. 
  332 
  (de- 
  

  

  scription) 
  

  

  In 
  the 
  north 
  this 
  species 
  is 
  the 
  earliest 
  of 
  the 
  genus 
  to 
  be 
  abroad 
  in 
  

   the 
  spring, 
  making 
  its 
  appearance 
  before 
  the 
  middle 
  of 
  May, 
  I 
  have 
  

   oftenest 
  found 
  the 
  imago 
  about 
  woodland 
  brooks 
  — 
  rarely 
  about 
  ponds. 
  

   I 
  have 
  never 
  found 
  the 
  nymph 
  ; 
  it 
  is 
  still 
  unknown. 
  

  

  