﻿[12] 
  REPORT 
  UNITED 
  STATES 
  ENTOMOLOGICAL 
  COMMISSION. 
  

  

  in 
  reality 
  tlieir 
  color 
  is 
  a 
  dirty 
  liglit-brown. 
  The 
  black-brown 
  color 
  of 
  the 
  

   male 
  abdomen 
  is 
  intermingled 
  with 
  the 
  light 
  pilosity 
  in 
  a 
  peculiar 
  man- 
  

   ner, 
  so 
  that 
  the 
  abdomen 
  has 
  already 
  been 
  called 
  "yellowish 
  -gray." 
  

  

  Another 
  remark 
  has 
  reference 
  to 
  the 
  instability 
  of 
  the 
  color 
  in 
  the 
  

   imago. 
  The 
  latter 
  manifests 
  in 
  this 
  relation 
  a 
  true 
  Proteus-nature 
  dur- 
  

   ing 
  the 
  first 
  few 
  hours 
  after 
  hatching. 
  The 
  abdomen 
  of 
  the 
  just-hatched 
  

   male 
  looks 
  dirty 
  — 
  looks 
  dirty 
  light-yellOw. 
  Into 
  this 
  yellow 
  soon 
  a 
  hue 
  

   of 
  red 
  mixes 
  itself, 
  and 
  after 
  an 
  hour 
  the 
  color 
  is 
  already 
  a 
  perfect 
  yellow- 
  

   red 
  one. 
  Through 
  fire-red 
  it 
  passes 
  into 
  a 
  dirty 
  light-brown, 
  and 
  thence 
  

   into 
  brown-red. 
  Kot 
  before 
  eight 
  or 
  ten 
  hours 
  is 
  the 
  fly 
  completely 
  col- 
  

   ored. 
  Not 
  less 
  striking 
  is 
  the 
  change 
  of 
  color 
  of 
  the 
  female, 
  an(^ 
  more 
  so 
  

   on 
  the 
  ventral 
  side. 
  Already 
  in 
  the 
  opened 
  pupa-shell 
  shortly 
  before 
  

   hatching 
  it 
  shows 
  a 
  shiny 
  brown-red 
  color, 
  which 
  passes 
  in 
  the 
  just- 
  

   hatched 
  fly 
  into 
  a 
  vivid 
  crimson, 
  thence 
  going 
  through 
  several 
  hues. 
  

   The 
  preserved 
  dead 
  female 
  after 
  some 
  time 
  scarcely 
  allows 
  us 
  to 
  distin- 
  

   guish 
  a 
  light 
  hue 
  on 
  the 
  joint-membranes 
  of 
  the 
  abdominal 
  segments. 
  

   I 
  will, 
  therefore, 
  indicate 
  the 
  color 
  in 
  the 
  description 
  of 
  the 
  imago 
  as 
  it 
  

   looked 
  to 
  me 
  under 
  the 
  microscope 
  in 
  the 
  comjpletely-colored, 
  recently 
  -Mlled 
  

   insect. 
  

  

  Male. 
  (Fig.15.) 
  — 
  Length 
  3°^°^. 
  Head 
  and 
  thorax 
  black 
  j 
  abdomenbrown- 
  

   black, 
  lighter 
  at 
  the 
  sides 
  ; 
  sutures 
  and 
  median 
  line 
  dorsally 
  usually 
  

   tawny 
  yellow. 
  Alar 
  radicles 
  and 
  immediate 
  surrounding 
  light 
  brown- 
  

   red. 
  Apart 
  from 
  the 
  wings 
  the 
  hairiness 
  of 
  all 
  the 
  other 
  body-parts 
  is 
  

   a 
  reddish 
  yellow. 
  Antennae 
  a 
  little 
  longer 
  than 
  half 
  the 
  body-length, 
  

   blackish, 
  turned 
  upward, 
  mouiliform; 
  hairs 
  verticillately 
  placed, 
  2-J-15- 
  

   to 
  2-f 
  17-jointed, 
  most 
  frequently 
  2-4-16-jointed. 
  First 
  basal 
  joint 
  be- 
  

   low 
  a 
  little 
  narrowed, 
  second 
  nearly 
  globular, 
  separated 
  from 
  the 
  lat- 
  

   ter 
  on]y 
  by 
  a 
  groove 
  ; 
  both 
  basal 
  joints 
  sparsely 
  bristled. 
  Knots 
  of 
  the 
  

   flagellar 
  joints 
  oval, 
  becoming 
  globular 
  toward 
  the 
  tips 
  j 
  style 
  of 
  the 
  

   flagellar 
  joints 
  only 
  a 
  third 
  thicker 
  but 
  over 
  two-thirds 
  longer 
  than 
  the 
  

   knots 
  which 
  are 
  scarcely 
  contracted 
  below 
  the 
  middle 
  ; 
  last 
  joint 
  sometimes 
  

   shorter 
  than 
  the 
  penultimate, 
  especially 
  when 
  the 
  number 
  of 
  flagellar 
  

   joints 
  attains 
  the 
  maximum 
  j 
  the 
  lower 
  verticillar 
  bristles 
  a 
  little 
  longer, 
  

   the 
  upper 
  just 
  as 
  long 
  as 
  the 
  single 
  joints. 
  Faceted 
  eyes 
  large, 
  lunate, 
  

   meeting 
  on 
  the 
  front. 
  Ocelli 
  and 
  pigment 
  eyes 
  do 
  not 
  occur. 
  Posterior 
  

   margin 
  of 
  the 
  head, 
  front, 
  and 
  lower 
  face 
  haired. 
  The 
  light-brown,, 
  

   short-haired 
  palpi 
  consist 
  of 
  four 
  unequally 
  long 
  joints 
  j 
  the 
  basal 
  joint 
  

   is 
  the 
  shortest 
  J 
  each 
  of 
  the 
  following 
  is 
  longer 
  than 
  its 
  preceding, 
  but 
  

   also 
  slenderer, 
  the 
  terminal 
  joint 
  as 
  long 
  as 
  the 
  second 
  and 
  third 
  

   together. 
  They 
  are 
  usually 
  directed 
  downward 
  and 
  curved, 
  so 
  that 
  

   each 
  of 
  them 
  represents 
  a 
  faint 
  curve 
  with 
  a 
  posteriorly 
  placed 
  concavity. 
  

   In 
  tftiis 
  position 
  they 
  make 
  themselves 
  conspicuous 
  by 
  active 
  vibra- 
  

   tion. 
  In 
  dead 
  specimens 
  we 
  find 
  the 
  palpi 
  frequently 
  bent 
  inward 
  or 
  

   crossing 
  each 
  other. 
  Between 
  the 
  palpi 
  protrudes 
  the 
  yellow 
  proboscis^ 
  

   usually 
  orally 
  retracted 
  towards 
  the 
  mouth 
  j 
  it^is 
  blunt, 
  ten-pin- 
  shaped, 
  

   of 
  about 
  the 
  length 
  and 
  thickness 
  of 
  the 
  second 
  palpal 
  joint. 
  A 
  trans- 
  

   verse, 
  in 
  life 
  vibrating, 
  bead 
  above 
  the 
  proboscis 
  I 
  take 
  to 
  be 
  the 
  upper 
  

   lip. 
  The 
  dorsal 
  part 
  of 
  the 
  thorax 
  (Brustrucken) 
  is 
  strongly 
  arched 
  lat- 
  

   erally, 
  beset 
  with 
  long 
  hairs; 
  the 
  whole 
  dorsal 
  surface 
  is 
  divided 
  into 
  

   three 
  shiny 
  areas 
  by 
  two 
  easily 
  rubbed, 
  longitudinal 
  hair-beads, 
  begin- 
  

   ning 
  behind 
  the 
  reddish 
  humeral 
  angle. 
  Scutellum 
  semicircular, 
  brown- 
  

   black, 
  with 
  its 
  posterior 
  margin 
  sparsely 
  haired. 
  Metathorax 
  naked. 
  

   "Wings 
  without 
  an 
  alula, 
  rounded 
  toward 
  tip, 
  wedge-shaped 
  at 
  base, 
  reach- 
  

   ing 
  far 
  beyond 
  the 
  abdomen, 
  gray 
  -turbid 
  ; 
  i)rovided 
  with 
  plain, 
  thin 
  hairs 
  

   directed 
  toward 
  the 
  tip. 
  The 
  anterior 
  margin 
  of 
  the 
  wing 
  is 
  beset 
  with 
  

   appressed 
  scale-like 
  hairs, 
  th« 
  posterior 
  margin 
  with 
  very 
  delicate 
  ciliate 
  

  

  