﻿The 
  British 
  Species 
  of 
  Andrena 
  and 
  Nomada. 
  ' 
  295 
  

  

  rugosity 
  over 
  the 
  whole 
  anterior 
  area 
  of 
  the 
  propodeum 
  

   as 
  in 
  that 
  species. 
  

  

  1. 
  (12) 
  Anterior 
  area 
  of 
  the 
  propodeum 
  strongly 
  rugose 
  and 
  always 
  

  

  bounded 
  posteriorly 
  just 
  on 
  the 
  brow 
  of 
  the 
  decUvity 
  

   by 
  a 
  raised 
  edge 
  or 
  transverse 
  rugosity 
  ; 
  the 
  species 
  that 
  

   have 
  the 
  2nd 
  abdominal 
  segment 
  glabrous 
  on 
  the 
  disc 
  

   lack 
  a 
  pattern 
  formed 
  by 
  dense 
  short 
  pale 
  hairs 
  on 
  the 
  

   apical 
  margins 
  of 
  the 
  3rd 
  and 
  4th 
  segments. 
  

   (Very 
  distinct 
  and 
  copious 
  abdominal 
  punctures 
  always 
  

   present.) 
  

  

  2. 
  (5) 
  Appressed 
  hairs 
  of 
  5th 
  abdominal 
  segment 
  golden 
  or 
  golden 
  

  

  red. 
  

  

  3. 
  (4) 
  Thorax 
  densely 
  clothed 
  with 
  bright 
  brown 
  or 
  fulvous 
  hairs. 
  

  

  albicans. 
  

  

  4. 
  (3) 
  Thorax 
  not 
  thus 
  clothed. 
  . 
  . 
  carbonaria 
  var. 
  praetexta. 
  

  

  5. 
  (2) 
  Appressed 
  hairs 
  of 
  5th 
  segment 
  black 
  or 
  dark 
  fuscous. 
  

  

  6. 
  (7) 
  Thorax 
  beneath 
  and 
  propodeum 
  at 
  the 
  sides 
  with 
  black 
  or 
  

  

  sooty 
  hairs, 
  scopae 
  beneath 
  silvery 
  white. 
  . 
  carbonaria. 
  

  

  7. 
  (6) 
  Thorax 
  beneath 
  propodeum 
  at 
  sides 
  not 
  black-haired, 
  scopae 
  

  

  not 
  silvery 
  white 
  beneath. 
  

  

  8. 
  (9) 
  Hind 
  tibiae 
  clear 
  yellow 
  or 
  reddish 
  beneath 
  the 
  scopa. 
  

  

  tibialis. 
  

  

  9. 
  (8) 
  Hind 
  tibiae 
  dark, 
  

  

  10. 
  (11) 
  Abdomen 
  more 
  or 
  less 
  red-marked 
  above 
  or 
  beneath. 
  

  

  bimaculata 
  and 
  var. 
  decorata. 
  

  

  11. 
  (10) 
  Abdomen 
  not 
  red-marked. 
  

  

  bimaculata 
  var. 
  conjuncta 
  and 
  var. 
  vitrea. 
  

  

  12. 
  (1) 
  Anterior 
  area 
  of 
  the 
  propodeum 
  rjirely 
  strongly 
  rugose 
  (the 
  

  

  rugosities 
  often 
  fading 
  out 
  posteriorly) 
  and 
  not 
  boimded 
  

   on 
  the 
  brow 
  of 
  the 
  declivity 
  by 
  a 
  raised 
  edge 
  or 
  trans- 
  

   verse 
  rugosity. 
  When 
  this 
  area 
  is 
  strongly 
  rugose 
  all 
  

   over, 
  the 
  abdomen 
  has 
  an 
  almost 
  glabrous 
  2nd 
  segment, 
  

   and 
  the 
  two 
  following 
  have 
  dense 
  pale 
  pubescent 
  streaks 
  

   on 
  their 
  apical 
  margins. 
  

  

  13. 
  (14) 
  Hind 
  tibiae 
  translucent 
  yellow, 
  the 
  mesonotum 
  and 
  

  

  scutellum 
  to 
  a 
  large 
  extent 
  at 
  least 
  with 
  black 
  hairs. 
  

  

  tarsata. 
  

  

  (Hind 
  tibiae 
  unusually 
  wide 
  at 
  the 
  apex 
  and 
  with 
  short 
  

  

  scopal 
  fringe 
  above, 
  abdomen 
  nearly 
  glabrous 
  above 
  with 
  

  

  more 
  or 
  less 
  distinct 
  bands 
  or 
  streaks 
  of 
  short 
  pale 
  hairs. 
  ) 
  

  

  14. 
  (13) 
  When 
  the 
  tibiae 
  are 
  clear 
  yellow, 
  the 
  thorax 
  is 
  not 
  largely 
  

  

  clothed 
  with 
  black 
  hairs. 
  

  

  15. 
  (16) 
  General 
  surface 
  of 
  the 
  abdomen 
  glabrous, 
  the 
  2nd, 
  3rd, 
  

  

  and 
  4th 
  segments 
  with 
  dense 
  pale 
  streaks 
  or 
  narrow 
  

  

  