﻿FREDERICINA 
  TESSERADACTYLA. 
  177 
  

  

  third 
  plumule 
  with 
  a 
  few 
  dark 
  scales 
  in 
  almost 
  same 
  position 
  as 
  in 
  that 
  of 
  

   calodactylar. 
  

  

  Variation. 
  — 
  This 
  small 
  ashy-grey 
  species 
  varies 
  apparently 
  but 
  

   little 
  in 
  size 
  and 
  colour. 
  In 
  tint, 
  some 
  examples 
  appear 
  paler 
  than 
  

   others 
  owing 
  to 
  the 
  extension 
  of 
  the 
  white 
  areas 
  in 
  the 
  centre 
  of 
  the 
  

   wing 
  and 
  outside 
  and 
  below 
  the 
  costal 
  triangle. 
  In 
  these 
  whiter 
  

   examples, 
  the 
  discal 
  lunule 
  stands 
  out 
  distinctly 
  (as 
  also 
  it 
  does 
  in 
  some 
  

   of 
  the 
  paler 
  F. 
  calodactyla) 
  along 
  the 
  base 
  of 
  the 
  costal 
  triangle 
  at 
  some 
  

   little 
  distance 
  from 
  the 
  fissure, 
  whilst, 
  in 
  the 
  more 
  grey 
  examples, 
  it 
  

   becomes 
  absorbed 
  in 
  the 
  costal 
  triangle 
  and 
  in 
  one 
  is 
  absent 
  altogether. 
  

   In 
  the 
  Frey 
  collection, 
  examples 
  from 
  the 
  Engadine 
  and 
  Zurich 
  

   appear 
  to 
  be 
  whiter 
  than 
  others 
  from 
  Silesia 
  and 
  Bossekop, 
  but 
  the 
  

   material 
  is 
  too 
  scanty 
  to 
  tempt 
  one 
  to 
  any 
  conclusions. 
  One 
  rather 
  

   suspects 
  that 
  there 
  is 
  considerable 
  variation, 
  in 
  this 
  respect, 
  within 
  

   somewhat 
  narrow 
  limits 
  in 
  most 
  localities. 
  Wocke 
  says 
  that 
  Finmark 
  

   specimens 
  from 
  Altenelv 
  are 
  somewhat 
  smaller 
  than, 
  but 
  otherwise 
  

   like, 
  German 
  examples. 
  Barrett 
  says 
  that 
  the 
  Irish 
  examples 
  are 
  

   whiter 
  than 
  continental 
  specimens, 
  with 
  the 
  dark 
  markings 
  grey 
  rather 
  

   than 
  brown, 
  the 
  Swiss 
  individuals 
  having 
  a 
  decidedly 
  warmer 
  tinge 
  of 
  

   colour 
  than 
  those 
  captured 
  in 
  Ireland. 
  We 
  append 
  Barrett's 
  descrip- 
  

   tion 
  of 
  the 
  Irish 
  specimens 
  : 
  — 
  

  

  a. 
  var. 
  hibernica, 
  n. 
  ab. 
  Tesseradactyla, 
  Barr., 
  " 
  Ent. 
  Mo. 
  Mag.," 
  xxxiii., 
  pp. 
  

   25, 
  62 
  (1897); 
  Kane, 
  "Ent.," 
  xxxi., 
  p. 
  209 
  (1898).— 
  Forewings 
  narrow 
  at 
  the 
  base, 
  

   but 
  rather 
  suddenly 
  broadened 
  behind 
  and 
  shortly 
  angulated 
  at 
  the 
  apex, 
  so 
  as 
  to 
  

   present 
  a 
  rather 
  stumpy 
  appearance; 
  pale 
  grey-brown 
  dusted 
  with 
  white, 
  and 
  

   having 
  two 
  oblique, 
  white, 
  transverse 
  stripes 
  towards 
  the 
  hind 
  margin, 
  one 
  of 
  them 
  

   crossing 
  the 
  base 
  of 
  the 
  fissure, 
  and 
  the 
  other 
  crossing 
  both 
  lobes 
  ; 
  immediately 
  

   before 
  the 
  first 
  of 
  these 
  is 
  the 
  usual 
  dark 
  costal 
  triangle, 
  of 
  a 
  dark 
  grey-brown 
  tint 
  ; 
  

   preceding 
  this, 
  in 
  the 
  middle 
  of 
  the 
  costal 
  margin, 
  is 
  a 
  small 
  dark 
  cloudy 
  spot, 
  a 
  

   pair 
  of 
  similar 
  spots 
  lies 
  on 
  the 
  dorsal 
  margin 
  before 
  the 
  middle 
  and 
  a 
  pair 
  of 
  

   minute 
  dark 
  dots 
  at 
  the 
  base 
  of 
  the 
  fissure 
  ; 
  cilia 
  sharply 
  white. 
  Hindwings 
  dark 
  

   fuscous 
  with 
  a 
  golden 
  gloss; 
  cilia 
  smoky-brown, 
  except 
  at 
  the 
  tip 
  of 
  each 
  lobe, 
  

   where 
  is, 
  in 
  each 
  case, 
  a 
  dash 
  of 
  pale 
  yellow 
  ; 
  on 
  the 
  dorsal 
  side 
  halfway 
  down 
  the 
  

   third 
  lobe 
  is 
  a 
  darker 
  fuscous 
  tuft 
  in 
  the 
  cilia. 
  Antennae 
  pale 
  brown, 
  barred 
  with 
  

   white; 
  head 
  and 
  front 
  of 
  thorax 
  pale 
  umbreous, 
  hinder 
  part 
  of 
  thorax 
  white; 
  

   abdomen 
  whitish-brown; 
  legs 
  whitish, 
  the 
  tibiae 
  of 
  the 
  hindmost 
  pair 
  having 
  a 
  

   brownish 
  cloudy 
  dash 
  before 
  each 
  pair 
  of 
  spurs. 
  It 
  bears 
  some 
  resemblance 
  to 
  

   Platyptilia 
  yonodactyla, 
  but 
  is 
  less 
  than 
  one-half 
  its 
  size, 
  being 
  in 
  fact 
  decidedly 
  

   smaller 
  than 
  the 
  occasional 
  dwarf 
  second-brood 
  specimens 
  of 
  that 
  species. 
  Hab. 
  : 
  

   Clonbrock 
  (Barrett). 
  

  

  The 
  American 
  form 
  is 
  described 
  by 
  Fernald 
  (Pter. 
  Nth. 
  America, 
  p. 
  33) 
  

   as 
  follows 
  : 
  — 
  

  

  Expanse 
  16mm. 
  -20mm. 
  Head, 
  palpi 
  and 
  frontal 
  tuft 
  greyish-brown. 
  Antennas 
  

   whitish, 
  dotted 
  above 
  with 
  dark 
  brown. 
  Thorax 
  grey 
  in 
  front, 
  white 
  behind. 
  

   Forewings 
  whitish, 
  heavily 
  dusted 
  with 
  brownish-grey. 
  The 
  somewhat 
  indistinct 
  

   brownish 
  triangle 
  on 
  the 
  outer 
  third 
  of 
  the 
  costa 
  is 
  followed 
  by 
  a 
  whitish 
  spot, 
  and 
  

   a 
  subterminal 
  white 
  line 
  crosses 
  both 
  lobes. 
  

  

  Comparison 
  of 
  Fredericina 
  tesseradactyla 
  with 
  its 
  allies. 
  — 
  

   Zeller 
  notes 
  (Linn. 
  Ent., 
  vi., 
  p. 
  337) 
  that 
  it 
  is 
  " 
  closely 
  related 
  to 
  

   gonodactyla, 
  zetterstedtii 
  and 
  nemoralis, 
  but 
  is 
  much 
  smaller 
  (forewings 
  

   from 
  4£'"-4J'"), 
  with 
  a 
  very 
  ill-developed 
  tuft 
  on 
  the 
  vertex 
  : 
  the 
  

   ground 
  colour 
  dusky 
  brownish 
  -grey, 
  without 
  yellowish 
  admixture, 
  and 
  

   always 
  with 
  sharply 
  denned 
  black-brown 
  transverse 
  streak 
  before 
  the 
  

   cleft 
  of 
  the 
  forewing." 
  Bofmann 
  writes 
  (Die 
  Deutsch. 
  Pteroph., 
  \\ 
  51) 
  : 
  

   " 
  The 
  smallest 
  Platyptiliid 
  ; 
  easily 
  separated 
  from 
  the 
  other 
  allied 
  

  

  * 
  These 
  scales 
  arc 
  particularly 
  easily 
  removed 
  in 
  this 
  speoies. 
  Some 
  other 
  

   wise 
  perfect 
  specimens 
  are 
  practically 
  without, 
  or 
  with 
  only 
  the 
  slightest 
  traces 
  ( 
  '. 
  

   them. 
  

  

  