﻿AQUATIC 
  INSECTS 
  IN 
  THE 
  ADIRONDACKS 
  503 
  

  

  casionally 
  one 
  would 
  sweep 
  out 
  into 
  the 
  forest 
  and 
  disappear 
  among 
  the 
  

   hemlocks. 
  

  

  The 
  nymphs 
  obtained 
  were 
  gathered 
  from 
  a 
  shaded 
  trashy 
  place 
  in 
  the 
  

   edge 
  of 
  Little 
  Clear 
  pond 
  and 
  from 
  Bone 
  pond. 
  They 
  lie 
  sprawling 
  

   amid 
  the 
  trash 
  after 
  the 
  manner 
  of 
  the 
  better 
  known 
  Libellulas. 
  

  

  I 
  did 
  not 
  rear 
  these 
  nymphs, 
  the 
  season 
  of 
  their 
  transformation 
  being 
  

   over, 
  apparently, 
  before 
  I 
  obtained 
  any 
  of 
  them. 
  I 
  kept 
  a 
  few 
  in 
  a 
  cage 
  

   through 
  the 
  greater 
  part 
  of 
  the 
  season 
  : 
  nevertheless, 
  there 
  is 
  not 
  the 
  

   slightest 
  doubt 
  as 
  to 
  their 
  identity. 
  They 
  agree 
  very 
  closely 
  with 
  the 
  

   nymphs 
  of 
  the 
  European 
  C. 
  a 
  en 
  e 
  a 
  Linn., 
  with 
  specimens 
  of 
  which 
  I 
  

   have 
  compared 
  them. 
  Male 
  nymphs 
  show 
  in 
  the 
  stretched 
  skin 
  of 
  the 
  

   superior 
  appendage 
  the 
  forked 
  tip 
  of 
  the 
  inferior 
  appendage 
  of 
  the 
  imago. 
  

   The 
  nymphs, 
  like 
  the 
  imagos, 
  were 
  in 
  numbers 
  second 
  only 
  to 
  the 
  Tet- 
  

   ragoneurias 
  among 
  the 
  Saranac 
  Cordulinae. 
  

  

  Nymph. 
  Total 
  length 
  21 
  mm; 
  abdomen 
  12 
  mm; 
  hind 
  femur 
  6.5 
  

   mm; 
  width 
  of 
  head 
  6 
  mm, 
  of 
  abdomen 
  7 
  mm. 
  

  

  Body 
  elongate, 
  sparsely 
  fringed 
  with 
  coarse 
  hairs 
  on 
  the 
  appendages, 
  

   edge 
  of 
  frons, 
  rear 
  of 
  head, 
  and 
  lateral 
  margins 
  of 
  abdomen; 
  color 
  

   greenish 
  brown 
  marked 
  with 
  blackish 
  brown 
  as 
  follows 
  : 
  a 
  tranverse 
  

   band 
  across 
  the 
  head 
  including 
  the 
  eyes 
  (almost 
  divided 
  by 
  the 
  median 
  

   yellow 
  ocellus 
  when 
  the 
  nymph 
  is 
  grown) 
  an 
  urceolate 
  median 
  band 
  on 
  

   the 
  prothorax 
  not 
  attaining 
  its 
  front 
  margin, 
  and 
  divided 
  by 
  a 
  fine 
  yellow 
  

   median 
  fine; 
  a 
  broad 
  oblique 
  lateral 
  yellow 
  band 
  extending 
  from 
  above 
  

   the 
  base 
  of 
  the 
  fore 
  leg 
  to 
  the 
  middle 
  of 
  the 
  hind 
  wing; 
  below 
  the 
  last, 
  a 
  

   narrower 
  parallel 
  stripe 
  above 
  the 
  base 
  of 
  the 
  hind 
  leg 
  ; 
  a 
  pair 
  of 
  sub- 
  

   median 
  rows 
  of 
  blotches 
  on 
  the 
  abdomen 
  extending 
  posteriorly 
  from 
  

   beneath 
  the 
  tips 
  of 
  the 
  hind 
  wings; 
  and 
  rings 
  on 
  femora 
  and 
  tibiae. 
  

  

  Head 
  with 
  the 
  eyes 
  laterally 
  prominent 
  and 
  well 
  rounded, 
  hind 
  angles 
  

   obtuse 
  and 
  the 
  hind 
  margin 
  slightly 
  concave; 
  no 
  vertical 
  tubercles; 
  

   frontal 
  ridge 
  low 
  obtuse; 
  labium 
  reaching 
  posteriorly 
  between 
  the 
  

   bases 
  of 
  the 
  second 
  pair 
  of 
  lesis, 
  triangular 
  elongate, 
  channeled 
  above 
  ; 
  

   median 
  lobe 
  prominent, 
  declined; 
  mental 
  setae 
  about 
  14, 
  regularly 
  

   graduated 
  in 
  size, 
  the 
  fourth 
  (counting 
  from 
  the 
  side) 
  longest; 
  lateral 
  

   setae 
  seven 
  ; 
  movable 
  hook 
  hardly 
  longer 
  than 
  the 
  setae, 
  nearly 
  straight 
  ; 
  

   teeth 
  about 
  nine, 
  low, 
  crenate, 
  increasing 
  in 
  breadth 
  inferiorly, 
  each 
  with 
  

   several 
  spinules. 
  

  

  Abdomen 
  oblong, 
  a 
  little 
  widened 
  to 
  the 
  seventh 
  segment, 
  most 
  

   narrowed 
  apically 
  on 
  the 
  ninth 
  segment; 
  loth 
  segment 
  annular, 
  half 
  as 
  

   wide 
  as 
  the 
  ninth, 
  and 
  one 
  fourth 
  to 
  one 
  third 
  as 
  long 
  as 
  the 
  ninth 
  is 
  on 
  

   its 
  middorsal 
  line 
  ; 
  ninth 
  segment 
  one 
  half 
  as 
  long 
  on 
  the 
  middorsal 
  line 
  

   as 
  on 
  the 
  midventral 
  ; 
  appendages 
  almost 
  equal, 
  the 
  superior 
  and 
  the 
  

   laterals 
  successively 
  a 
  very 
  little 
  shorter 
  than 
  the 
  inferiors, 
  which 
  are 
  

   about 
  as 
  long 
  as 
  segment 
  9 
  is 
  on 
  its 
  dorsal 
  side; 
  lateral 
  spines 
  on 
  

   segments 
  8 
  and 
  9 
  very 
  short 
  (about 
  one 
  fifth 
  the 
  length 
  of 
  the 
  body 
  of 
  

   the 
  segments 
  which 
  bear 
  them), 
  but 
  pyramidal. 
  

  

  The 
  first 
  cast 
  nymph 
  skin 
  was 
  obtained 
  June 
  16. 
  The 
  imagos 
  were 
  

   flying 
  commonly 
  throughout 
  the 
  month 
  of 
  July. 
  

  

  