﻿510 
  Mr. 
  T. 
  D. 
  A. 
  Cockerell 
  — 
  Descriptions 
  and 
  

  

  Halictus 
  instahUis, 
  sp, 
  n. 
  

  

  $ 
  . 
  — 
  Length 
  about 
  8 
  ram. 
  

  

  Black, 
  robust, 
  with 
  greyish-wliite 
  hair, 
  mixed 
  with 
  fuscous 
  

   on 
  vertex^ 
  mesothorax, 
  and 
  scutellum 
  ; 
  mandibles 
  very 
  faintly 
  

   reddish 
  subapically 
  ; 
  cl\peus 
  shining, 
  with 
  irregular, 
  not 
  

   very 
  large 
  punctures, 
  and 
  no 
  median 
  depression 
  ; 
  sides 
  of 
  

   front 
  glistening, 
  but 
  middle 
  broadly 
  dull 
  black, 
  excessively 
  

   closely 
  punctured 
  ; 
  flagellum 
  dark 
  ; 
  anterior 
  angles 
  of 
  pro- 
  

   thorax 
  rather 
  prominent 
  ; 
  mesothorax 
  shining, 
  with 
  very 
  

   fine 
  but 
  distinct 
  punctures 
  ; 
  scutellum 
  broad 
  and 
  flattened, 
  

   very 
  minut(.'ly 
  ])unctured 
  ; 
  area 
  of 
  metathorax 
  rather 
  short, 
  

   well 
  defined, 
  finely 
  plicate, 
  with 
  a 
  band 
  of 
  subbasal 
  fine 
  

   connecting 
  ridges 
  ; 
  in 
  the 
  whole 
  middle 
  area 
  the 
  plicse 
  are 
  

   veiy 
  fine 
  and 
  irregular, 
  and 
  the 
  surface 
  between 
  them 
  is 
  

   minutely 
  pitted 
  ; 
  posterior 
  truncation 
  not 
  shar[)ly 
  defined 
  at 
  

   sides 
  ; 
  pleura 
  very 
  hairy. 
  Legs 
  piceous, 
  with 
  glistening 
  

   light 
  hair, 
  the 
  hind 
  tibiae 
  with 
  a 
  band 
  of 
  greyish-fuscous 
  

   hair 
  on 
  outer 
  side 
  ; 
  hind 
  spur 
  like 
  that 
  of 
  H. 
  griseovittatus 
  ; 
  

   tegulse 
  piceous, 
  with 
  a 
  large 
  rufous 
  spot. 
  Wings 
  dusky, 
  

   greyish, 
  stigma 
  and 
  nervures 
  dull 
  reddish, 
  second 
  s.m. 
  higher 
  

   than 
  broad, 
  first 
  r. 
  n. 
  meeting 
  second 
  t.-c. 
  Abdomen 
  broad, 
  

   shining, 
  very 
  finely 
  punctured, 
  bases 
  of 
  segments 
  with 
  

   greyish-white 
  tomentum 
  as 
  in 
  H. 
  griseovittatus, 
  but 
  the 
  

   bands 
  have 
  a 
  slightly 
  ochreous 
  tint. 
  

  

  Hub. 
  Croydon, 
  Victoria 
  {Miss 
  A. 
  M. 
  Fulton 
  ; 
  Nat. 
  Mus. 
  

   Vict. 
  77). 
  

  

  Variety 
  a. 
  

  

  Stigma 
  clearer 
  red 
  ; 
  second 
  s.m. 
  very 
  broad, 
  broader 
  

   below 
  than 
  high 
  ; 
  wings 
  slightly 
  reddish 
  ; 
  area 
  of 
  metathorax 
  

   longer. 
  

  

  Hab. 
  '^ 
  Windsor, 
  Victoria^' 
  {French 
  ; 
  Froggatt 
  coll. 
  191). 
  

  

  Variety 
  b. 
  

  

  Wings 
  practically 
  as 
  in 
  variety 
  a, 
  with 
  broad 
  second 
  sub- 
  

   marginal 
  cell 
  ; 
  postscutellum 
  longer, 
  subangulate 
  behind 
  ; 
  

   area 
  of 
  metathorax 
  sharply 
  defined, 
  with 
  stronger 
  plicse. 
  

  

  Hab. 
  Victoria, 
  Sept. 
  1901 
  {C 
  F. 
  ; 
  Turner 
  coll.). 
  

  

  Closely 
  related 
  to 
  H. 
  griseovittatus, 
  but 
  larger, 
  with 
  the 
  

   bands 
  on 
  the 
  abdomen 
  diflerently 
  coloured. 
  Possibly 
  

   variety 
  b 
  is 
  a, 
  distinct 
  species, 
  but 
  I 
  hesitate 
  to 
  separate 
  it, 
  

   especially 
  since 
  var. 
  a 
  is 
  intermediate 
  between 
  it 
  and 
  the 
  

   type. 
  

  

  