﻿166 
  BRUCE 
  F* 
  CUMMINGS. 
  

  

  angles, 
  two 
  widely-spaced 
  minute 
  hairs. 
  On 
  the 
  ventral 
  surface, 
  two 
  longitudinal 
  

   rows 
  Of 
  hairs, 
  four 
  or 
  five 
  in 
  each 
  row, 
  running 
  from 
  the 
  submentum 
  to 
  the 
  occiput. 
  

   On 
  the 
  premandibular 
  cushion 
  there 
  are 
  12 
  spines 
  on 
  the 
  anterior 
  margin, 
  the 
  outside 
  

   ones 
  being 
  the 
  longest, 
  and 
  16 
  smaller 
  ones, 
  more 
  closely 
  spaced 
  but 
  with 
  larger 
  alveoli, 
  

   on 
  the 
  posterior 
  margin. 
  Just 
  behind 
  the 
  posterior 
  margin 
  of 
  the 
  cushion 
  and 
  near 
  the 
  

   tips 
  of 
  the 
  mandibles 
  are 
  two 
  small 
  denticles, 
  each 
  of 
  them 
  bifid. 
  Thorax 
  : 
  Anterior 
  

   margin 
  of 
  pronotum 
  with 
  a 
  small 
  hair, 
  just 
  outside 
  the 
  occipital 
  hole. 
  The 
  angles 
  

   of 
  the 
  lateral 
  wings 
  each 
  with 
  two 
  short 
  spines, 
  one 
  below 
  the 
  other 
  ; 
  two 
  more 
  

   behind, 
  one 
  below 
  the 
  other. 
  The 
  posterior 
  margin 
  of 
  the 
  pronotum 
  with 
  a 
  row 
  of 
  

   well-spaced 
  hairs 
  of 
  medium 
  length. 
  Just 
  inside 
  the 
  wing, 
  at 
  each 
  end 
  of 
  the 
  trans- 
  

   verse 
  line, 
  a 
  small 
  hair. 
  Lateral 
  margins 
  of 
  the 
  metanotum 
  with 
  many 
  short 
  hairs. 
  

   Other 
  hairs 
  arranged 
  as 
  in 
  the 
  figure. 
  The 
  legs 
  are 
  noticeable 
  for 
  a 
  patch 
  of 
  thick 
  

   hairs 
  on 
  the 
  lower 
  surface 
  of 
  the 
  hind 
  femur. 
  Abdomen 
  : 
  Tergites 
  each 
  with 
  two 
  

   irregular 
  rows 
  of 
  well-spaced 
  hairs 
  of 
  medium 
  length, 
  except 
  the 
  ninth, 
  which 
  is 
  bare. 
  

   Pleurae 
  with 
  longer 
  hairs, 
  one 
  being, 
  as 
  a 
  rule, 
  much 
  longer 
  than 
  the 
  rest. 
  Pleurae 
  

   of 
  segment 
  8 
  with 
  two 
  long 
  hairs. 
  The 
  lateral 
  margins 
  of 
  the 
  terminal 
  segment 
  with 
  

   six 
  hairs 
  on 
  each 
  side, 
  the 
  last 
  one 
  being 
  very 
  long 
  ; 
  the 
  apical 
  margin 
  with 
  eight 
  or 
  

   nine 
  smaller 
  hairs. 
  Sternites 
  3 
  to 
  7 
  with 
  a 
  patch 
  of 
  short 
  hairs 
  crowded 
  together 
  

   on 
  each 
  side 
  of 
  the 
  middle 
  fine, 
  well 
  within 
  the 
  lateral 
  margin. 
  Sternites 
  2 
  and 
  3 
  

   with 
  a 
  number 
  of 
  fairly 
  small, 
  irregularly 
  arranged 
  hairs, 
  present 
  also 
  on 
  the 
  other 
  

   sternites, 
  between 
  the 
  right 
  and 
  left 
  patches. 
  Lower 
  lip 
  of 
  the 
  opening 
  to 
  the 
  genital 
  

   chamber 
  with 
  numerous 
  long 
  bristles. 
  

  

  Chaetotaxy, 
  Female 
  (fig. 
  5). 
  — 
  Abdomen 
  : 
  Tergites 
  bare 
  except 
  those 
  of 
  segments 
  

   8 
  and 
  9, 
  on 
  the 
  former 
  of 
  which 
  there 
  is 
  a 
  row 
  of 
  hairs 
  on 
  the 
  posterior 
  margin, 
  and 
  

   on 
  the 
  latter, 
  numerous 
  small 
  somewhat 
  scattered 
  hairs 
  arranged 
  in 
  an 
  irregular 
  row. 
  

   Sternites 
  as 
  in 
  the 
  male. 
  Genital 
  plate 
  bare, 
  but 
  covered 
  by 
  the 
  cluster 
  of 
  hairs 
  which 
  

   are 
  situated 
  on 
  the 
  plate 
  in 
  front 
  of 
  it. 
  Integument 
  dorsally 
  and 
  ventrally 
  covered 
  

   with 
  an 
  immense 
  number 
  of 
  minute 
  denticles, 
  like 
  the 
  skin 
  of 
  a 
  dogfish. 
  Pleurae 
  

   with 
  many 
  short 
  spines. 
  Pleurae 
  of 
  segments 
  2, 
  4, 
  6 
  and 
  7 
  each 
  with 
  a 
  single 
  long 
  

   hair, 
  8 
  with 
  two 
  long 
  hairs. 
  Terminal 
  margin 
  of 
  the 
  abdomen 
  with 
  four 
  powerful 
  

   spines 
  on 
  each 
  side 
  and 
  one 
  long 
  hair 
  on 
  the 
  inside 
  of 
  these 
  ; 
  between 
  these 
  two 
  longer 
  

   hairs 
  are 
  numerous 
  less 
  powerful 
  spines. 
  Lip 
  of 
  the 
  opening 
  to 
  the 
  genital 
  chamber 
  

   closely 
  set 
  with 
  numerous 
  spiny 
  hairs. 
  

  

  Colouration. 
  — 
  Both 
  sexes 
  are 
  white 
  above 
  ; 
  eyes 
  black. 
  On 
  the 
  ventral 
  surface 
  

   the 
  male 
  has 
  the 
  sternites 
  of 
  the 
  thorax 
  dark 
  brown 
  or 
  black. 
  The 
  abdominal 
  sternites 
  

   also 
  show 
  in 
  most 
  specimens 
  an 
  irregular, 
  dark 
  brown 
  patch 
  on 
  each 
  side. 
  The 
  

   ventral 
  surface 
  of 
  the 
  female 
  is 
  coloured 
  as 
  follows 
  : 
  — 
  Tips 
  of 
  mandibles 
  black 
  ; 
  

   two 
  black 
  marks 
  on 
  each 
  side 
  of 
  the 
  occiput 
  ; 
  prosternite 
  brown, 
  lateral 
  bands 
  in 
  the 
  

   mesosternal 
  region 
  black 
  ; 
  abdominal 
  pleurae 
  each 
  with 
  a 
  heavy, 
  dark 
  brown, 
  longi- 
  

   tudinal 
  band 
  ; 
  each 
  sternite 
  banded 
  transversely 
  with 
  brown, 
  paler 
  in 
  the 
  middle. 
  

  

  Mouth-parts 
  (fig. 
  4, 
  a, 
  b). 
  — 
  Labium 
  : 
  The 
  submentum 
  is 
  a 
  well-marked 
  broad 
  

   rectangular 
  plate. 
  The 
  mentum 
  carries 
  two 
  small 
  lobes, 
  usually 
  called 
  paraglossae. 
  

   Between 
  these 
  are 
  two 
  slight 
  projections 
  carrying 
  several 
  small 
  hairs. 
  Isopogometric 
  

   apparatus* 
  : 
  The 
  anterior 
  cornua 
  of 
  the 
  oesophageal 
  sclerite 
  (or 
  lyriform 
  organ), 
  

  

  * 
  See 
  E. 
  Armenante 
  (10). 
  

  

  