﻿f 
  AQUATIC 
  INSECTS 
  IN 
  THE 
  ADIRONDACKS 
  425. 
  

  

  Color 
  yellowish 
  or 
  greenish 
  brown, 
  mottled 
  with 
  blackish 
  brown 
  on 
  the 
  

   dorsal 
  side 
  in 
  a 
  pattern 
  of 
  short 
  streaks. 
  Legs 
  yellowish 
  : 
  femora 
  with 
  

   a 
  band 
  of 
  brown 
  just 
  beyond 
  the 
  middle; 
  other 
  brownish 
  marks 
  beside 
  

   or 
  on 
  all 
  the 
  leg 
  sutures 
  ; 
  tibia 
  shorter 
  than 
  the 
  tarsus 
  without 
  its 
  claw.. 
  

  

  Setae 
  yellow, 
  with 
  a 
  whitish 
  fringe 
  of 
  hairs 
  of 
  silky 
  aspect; 
  a 
  trans- 
  

   verse 
  band 
  of 
  brown 
  across 
  them 
  just 
  beyond 
  the 
  middle, 
  and 
  a 
  brownish 
  

   shade 
  near 
  the 
  tip. 
  

  

  Gills 
  present 
  and 
  double 
  on 
  segments 
  1-7 
  ; 
  the 
  posterior 
  leaf 
  with 
  a 
  

   chitinous 
  ridge 
  on 
  its 
  ventral 
  (external) 
  margin, 
  not 
  reaching 
  the 
  apex^ 
  

   relatively 
  shortest 
  on 
  the 
  first 
  gill 
  ; 
  the 
  posterior 
  leaf 
  trilobed 
  on 
  segment 
  

   I, 
  bilobed 
  on 
  segments 
  2-6, 
  and 
  simple 
  on 
  segment 
  7 
  ; 
  the 
  smaller, 
  

   thinner 
  and 
  more 
  delicate 
  anterior 
  leaf 
  bilobed 
  on 
  segments 
  i 
  and 
  2, 
  

   simple 
  on 
  segments 
  3-7, 
  becoming 
  very 
  small 
  on 
  the 
  seventh 
  segment. 
  

  

  In 
  contrast 
  with 
  the 
  gills 
  of 
  Heptagenia, 
  in 
  which 
  the 
  anterior 
  

   leaf 
  of 
  the 
  gill 
  is 
  thickened 
  and 
  protects 
  the 
  delicate 
  posterior 
  one, 
  we 
  

   have 
  in 
  Siphlurus 
  the 
  anterior 
  leaf 
  thin 
  and 
  dehcate, 
  the 
  posterior 
  one 
  

   thickened. 
  The 
  latter, 
  having 
  muscles 
  attached 
  to 
  it 
  internally, 
  thus 
  

   becomes 
  a 
  swimming 
  organ, 
  capable 
  of 
  a 
  smart 
  backward 
  stroke. 
  Each 
  

   acts 
  in 
  concert 
  with 
  its 
  fellows 
  and 
  with 
  the 
  tail 
  fin, 
  producing 
  a 
  racing 
  

   speed 
  for 
  a 
  Accession 
  of 
  short 
  dashes 
  through 
  the 
  water. 
  The 
  respira- 
  

   tory 
  gill 
  leaf, 
  being 
  placed 
  at 
  the 
  front, 
  is 
  out 
  of 
  the 
  way 
  of 
  the 
  stroke. 
  

  

  Two 
  specimens 
  of 
  Callibaetis 
  ferruginea 
  were 
  taken 
  at 
  the 
  

   hatchery 
  windows 
  during 
  the 
  month 
  of 
  August. 
  

  

  Ephemerella 
  excurcians 
  Walsh 
  

  

  1862 
  Ephemerel 
  ] 
  a 
  excruci 
  an 
  8 
  Walsh, 
  Acad, 
  n 
  at. 
  .sci. 
  Phil. 
  Proc. 
  p. 
  37T 
  

  

  (original 
  description) 
  

  

  1863 
  Ephemerella 
  excrucians 
  Hagen, 
  Ent. 
  soc. 
  Phil. 
  Proc. 
  2 
  :178 
  (note> 
  

   1885 
  Ephemerella 
  excrucians 
  Eaton, 
  Linn. 
  soc. 
  Lond. 
  Trans. 
  3: 
  130 
  (a 
  

  

  full 
  description) 
  

   1892 
  Eph 
  emer 
  ella 
  excrucians 
  Banks, 
  Am. 
  ent. 
  soc. 
  Trans. 
  19:347 
  

  

  (listed) 
  

   1871 
  Ephemerella 
  invaria, 
  in 
  part, 
  Eaton, 
  Ent. 
  soc. 
  Lond. 
  Trans, 
  p. 
  100^ 
  

  

  Very 
  few 
  imagos 
  of 
  this 
  interesting 
  species 
  were 
  obtained, 
  notwith- 
  

   standing 
  the 
  nymphs 
  were 
  common 
  in 
  Little 
  Clear 
  creek 
  and 
  even 
  in- 
  

   the 
  hatchery 
  troughs 
  during 
  the 
  month 
  of 
  July. 
  A 
  single 
  pair 
  was 
  bre(J' 
  

   July 
  10, 
  transforming 
  to 
  imagos 
  the 
  following 
  day. 
  Specimens 
  were 
  

   taken 
  at 
  the 
  trap 
  lantern 
  and 
  from 
  the 
  hatchery 
  windows. 
  The 
  species 
  

   is 
  known 
  from 
  New 
  York, 
  Ilhnois 
  and 
  Michigan. 
  

  

  The 
  nymph 
  is 
  no. 
  5 
  of 
  Eaton's 
  monograph. 
  ^ 
  This 
  being 
  the 
  type 
  

   species 
  of 
  the 
  genus 
  Ephemerella, 
  a 
  genus 
  the 
  nymphs 
  of 
  which 
  

   show 
  considerable 
  differences, 
  it 
  is 
  the 
  more 
  desirable 
  that 
  the 
  immature 
  

   stages 
  should 
  be 
  made 
  known. 
  

  

  iLlnn. 
  soc. 
  Lond. 
  Trans. 
  1885. 
  3 
  : 
  133-34, 
  pi, 
  40, 
  flg. 
  18-20, 
  and 
  pi. 
  64, 
  fig. 
  3-7. 
  Unknown 
  genus 
  

   **allledto 
  Ephemerella." 
  

  

  