﻿268 
  EEPORT 
  UNITED 
  STATES 
  ENTOMOLOGICAL 
  COMMISSION. 
  

  

  which 
  is 
  protuberant 
  and 
  laid 
  along 
  the 
  breast, 
  extending 
  to 
  near 
  the 
  tips 
  of 
  the 
  wings 
  ; 
  

   the 
  face 
  with 
  two 
  parallel 
  depressions 
  running 
  from 
  between 
  the 
  triple 
  tubercles 
  and 
  

   ending 
  in 
  two 
  fossae 
  above 
  the 
  frontal 
  spines 
  ; 
  two 
  basal, 
  medio-dorsal 
  tubercles. 
  Thorax 
  

   unarmed, 
  the 
  prothoracic 
  spiracle 
  very 
  large 
  and 
  raised 
  on 
  a 
  curved 
  tubercle 
  ; 
  meso- 
  

   thoracic 
  spiracle 
  on 
  a 
  swelling 
  at 
  base 
  of 
  wings; 
  front 
  tibiae 
  stout 
  and 
  curved; 
  front 
  

   tarsi 
  reaching 
  to 
  tips 
  of 
  wings; 
  middle 
  tarsi 
  to 
  abdominal 
  joint 
  beyond, 
  and 
  hind 
  tarsi 
  

   to 
  third 
  abdominal 
  joint 
  beyond. 
  Abdomen 
  curved, 
  with 
  the 
  ninth 
  joint 
  very 
  small 
  ; 
  

   across 
  the 
  middle, 
  dorsally, 
  each 
  joint 
  has 
  a 
  series 
  of 
  parallel, 
  longitudinal, 
  narrow, 
  

   chitinous 
  plates 
  having 
  at 
  each 
  extremity 
  a 
  spine, 
  the 
  posterior 
  one 
  stoutest 
  ; 
  both 
  

   plates 
  and 
  spines 
  diminishing 
  laterally, 
  gradually 
  aborted 
  on 
  the 
  extreme 
  basal 
  and 
  

   posterior 
  joints, 
  and 
  replaced 
  on 
  the 
  small 
  ninth 
  joint 
  by 
  a 
  group 
  of 
  four 
  converging 
  

   and 
  truncate 
  tubercles; 
  two 
  stouter 
  anal 
  spines 
  on 
  the 
  subjoint 
  and 
  a 
  ventral 
  lobe 
  

   with 
  two 
  short, 
  obscurely 
  articulate 
  processes; 
  each 
  abdominal 
  joint 
  with 
  a 
  circle 
  of 
  

   hairs, 
  those 
  on 
  lateral 
  ridge 
  stoutest 
  and 
  one-third 
  the 
  width 
  of 
  abdomen 
  in 
  length 
  ; 
  8 
  

   pair 
  of 
  abdominal 
  spiracles 
  (making 
  10 
  with 
  those 
  on 
  thorax), 
  the 
  first 
  and 
  last 
  pairs 
  

   rather 
  difficult 
  of 
  detection. 
  

  

  Imago. 
  — 
  The 
  perfect 
  fly 
  (PI. 
  XVI, 
  Fig. 
  3) 
  is 
  at 
  once 
  distinguished 
  from 
  the 
  succeed- 
  

   ing 
  species 
  by 
  its 
  broader 
  form 
  and 
  long 
  proboscis. 
  The 
  whole 
  body 
  is 
  covered 
  with 
  

   long 
  yellow 
  or 
  fulvous 
  hairs. 
  The 
  species 
  varies 
  in 
  the 
  color 
  of 
  the 
  legs 
  and 
  in 
  size, 
  

   some 
  females 
  being 
  larger 
  than 
  the 
  males. 
  The 
  species 
  was 
  originally 
  described 
  from 
  

   Sierra 
  County, 
  California, 
  and 
  Mr. 
  Williston 
  informs 
  us 
  that 
  he 
  has 
  a 
  specimen 
  from 
  

   Washington 
  Territory. 
  We 
  quote 
  Osten 
  Sacken's 
  original 
  description 
  : 
  

  

  Systoechus 
  ore 
  as. 
  — 
  Differs 
  from 
  S. 
  vulgaris 
  in 
  the 
  third 
  antennal 
  joint 
  being 
  a 
  

   little 
  broader, 
  the 
  mystax 
  being 
  more 
  mixed 
  with 
  fulvous 
  pile, 
  the 
  proboscis 
  longer, 
  

   the 
  legs 
  darker, 
  the 
  wings 
  more 
  grayish, 
  the 
  covering 
  of 
  pile 
  more 
  dense 
  and 
  of 
  a 
  

   paler 
  shade 
  of 
  yellow, 
  the 
  ground-color 
  less 
  dark 
  (when 
  denuded), 
  without 
  reddish 
  on 
  

   the 
  scutellnm; 
  on 
  the 
  average, 
  the 
  size 
  is 
  somewhat 
  larger. 
  

  

  Male.— 
  The 
  blackish 
  -gray 
  ground-color 
  of 
  the 
  body 
  is 
  entirely 
  concealed 
  (in 
  intact 
  

   specimens) 
  under 
  a 
  thick 
  covering 
  of 
  pale 
  yellow 
  pile, 
  giving 
  the 
  body 
  an 
  elongated- 
  

   oval 
  shape, 
  slightly 
  broader 
  about 
  the 
  middle 
  of 
  the 
  abdomen 
  ; 
  face 
  and 
  front 
  covered 
  

   with 
  a 
  recumbent 
  fulvous 
  tomentum, 
  and 
  erect 
  black 
  pile 
  ; 
  mystax 
  mixed 
  of 
  both 
  ; 
  

   some 
  black 
  pile 
  on 
  the 
  vertex; 
  antennae 
  black, 
  third 
  joint 
  considerably 
  expanded 
  on 
  

   its 
  proximal 
  half; 
  legs 
  black; 
  femora 
  densely 
  covered 
  with 
  the 
  usual 
  appressed 
  whit- 
  

   ish 
  hairs, 
  which 
  conceal 
  the 
  ground-color; 
  tibiae 
  reddish, 
  but 
  clothed 
  with 
  the 
  same 
  

   whitish 
  pubescence 
  ; 
  the 
  latter 
  part 
  of 
  the 
  tibiae 
  is 
  black, 
  and 
  on 
  the 
  inner 
  side 
  this 
  

   «olor 
  extends 
  farther 
  upward 
  than 
  externally; 
  tarsi 
  deep 
  black. 
  Wings 
  with 
  a 
  

   decidedly 
  grayish 
  tinge, 
  brownish-yellow 
  at 
  the 
  base 
  and 
  in 
  the 
  costal 
  and 
  first 
  basal 
  

   cells. 
  Length 
  about 
  10 
  mm 
  (including 
  the 
  length 
  of 
  the 
  pile 
  at 
  both 
  ends 
  of 
  the 
  body, 
  

   but 
  excluding 
  the 
  antennae). 
  

  

  Female. 
  — 
  I 
  have 
  a 
  single 
  somewhat 
  damaged 
  specimen, 
  which 
  evidently 
  belongs 
  

   here, 
  although 
  it 
  is 
  smaller, 
  and 
  the 
  femora 
  and 
  tibiae, 
  except 
  the 
  tip, 
  are 
  yellowish- 
  

   red. 
  Length 
  about 
  8 
  mm 
  . 
  

  

  Sab. 
  — 
  Webber 
  Lake, 
  Sierra 
  County, 
  California, 
  July 
  22-26. 
  Three 
  males 
  and 
  one 
  

   iemale. 
  None 
  of 
  my 
  specimens 
  show 
  any 
  reddish 
  on 
  the 
  scutellum. 
  

  

  Triodites 
  mus. 
  

  

  The 
  habits 
  of 
  this 
  insect 
  in 
  the 
  larva 
  state 
  are 
  precisely 
  like 
  those 
  of 
  

   the 
  preceding. 
  

  

  Larva 
  (PI. 
  XVI, 
  Fig. 
  4). 
  — 
  So 
  greatly 
  resembling 
  that 
  of 
  the 
  Systoechus 
  that 
  it 
  is 
  well 
  

   nigh 
  impossible 
  to 
  separate 
  the 
  two 
  with 
  certainty. 
  The 
  head 
  parts 
  are 
  somewhat 
  

   broader, 
  shorter, 
  and 
  less 
  flattened, 
  the 
  maxillae 
  more 
  blunt, 
  the 
  labrum 
  paler, 
  and 
  the 
  

   mandibles 
  sharper 
  and 
  with 
  a 
  smoother 
  outer 
  edge. 
  The 
  thoracic 
  joints 
  bulge 
  less 
  

   beneath 
  and 
  the 
  thoracic 
  spiracle 
  is 
  more 
  sunken 
  and 
  less 
  conspicuous. 
  

  

  Pupa 
  (PI. 
  XVI, 
  Fig. 
  5). 
  — 
  Easily 
  distinguished 
  from 
  that 
  of 
  Systoechus 
  in 
  the 
  broader 
  

   and 
  more 
  bulbous 
  head 
  ; 
  in 
  the 
  two 
  sets 
  of 
  three 
  stout 
  spines 
  at 
  top 
  being 
  well 
  sepa- 
  

   rated 
  ; 
  in 
  the 
  frontal 
  pair 
  being 
  stouter, 
  each 
  with 
  a 
  conspicuous 
  bristle 
  externally 
  ; 
  

   in 
  having 
  a 
  single 
  spine 
  or 
  tooth 
  above 
  these, 
  and 
  another 
  much 
  stouter, 
  erect, 
  re- 
  

   curved 
  spiue, 
  bidentate 
  at 
  tij>, 
  below 
  them 
  or 
  at 
  base 
  of 
  tongue, 
  which 
  is 
  here 
  repre- 
  

   sented 
  by 
  a 
  cordate 
  lobe. 
  There 
  is 
  a 
  spine 
  on 
  the 
  front 
  anterior 
  border 
  of 
  each 
  wing 
  ; 
  

  

  