﻿The 
  British 
  Species 
  of 
  Andrena 
  and 
  Nomada. 
  227 
  

  

  being 
  dark 
  or 
  fuscous, 
  becomes 
  yellow 
  or 
  golden. 
  Such 
  are 
  

   the 
  var. 
  consimilis 
  Sni. 
  of 
  A. 
  nitida 
  and 
  the 
  var. 
  praetexta 
  of 
  

   A. 
  carbonaria, 
  while 
  among 
  species 
  that 
  have 
  a 
  yellow 
  scopa 
  

   but 
  normally 
  a 
  more 
  or 
  less 
  fuscous 
  fimbria 
  there 
  is 
  a 
  form 
  of 
  

   A 
  . 
  tarsata, 
  in 
  which 
  the 
  latter 
  is 
  a 
  bright 
  pale 
  golden 
  colour, 
  

   and 
  similar 
  forms 
  of 
  A. 
  ovatula 
  also 
  occur. 
  In 
  some 
  species, 
  

   e.g., 
  A.fucata, 
  the 
  scopa 
  may 
  become 
  quite 
  pale 
  without 
  the 
  

   fimbria 
  being 
  affected. 
  The 
  entire 
  replacement 
  of 
  black 
  

   hairs 
  by 
  white 
  in 
  varians 
  var. 
  mixta 
  has 
  already 
  been 
  men- 
  

   tioned, 
  and 
  the 
  change 
  from 
  white 
  hairs 
  on 
  the 
  face 
  to 
  fus- 
  

   cous 
  or 
  blackish 
  ones 
  occurs 
  in 
  A. 
  nitida 
  var. 
  baltica, 
  common 
  

   in 
  Devonshire, 
  and 
  also 
  in 
  some 
  specimens 
  of 
  angustior 
  and 
  

   others. 
  Hermaphrodites 
  of 
  A.Jlavipes 
  (ftdvicrus), 
  bimacu- 
  

   lata, 
  dorsata 
  and 
  albicans 
  have 
  been 
  described 
  by 
  myself, 
  and 
  

   one 
  of 
  A. 
  nitida 
  by 
  Smith. 
  

  

  Extraordinary 
  variation 
  in 
  size 
  is 
  a 
  remarkable 
  feature 
  

   of 
  the 
  males 
  of 
  many 
  Andrenas, 
  but 
  in 
  the 
  females 
  this 
  

   is 
  much 
  less 
  marked 
  and 
  of 
  a 
  different 
  nature. 
  In 
  the 
  

   latter 
  sex 
  there 
  is 
  usually 
  a 
  fairly 
  average 
  size 
  in 
  the 
  largest 
  

   specimens, 
  while 
  quite 
  abnormally 
  small, 
  or 
  starved 
  ones, 
  

   are 
  found 
  occasionally. 
  In 
  the 
  males, 
  on 
  the 
  contrary, 
  

   whereas 
  there 
  is 
  great 
  general 
  variability 
  in 
  the 
  size, 
  in 
  

   many 
  species 
  gigantic 
  examples 
  are 
  occasionally 
  met 
  with. 
  

   This 
  phenomenon 
  is 
  not 
  at 
  all 
  uncommon, 
  and 
  there 
  is 
  

   nothing 
  Like 
  it 
  in 
  the 
  $ 
  sex. 
  Where 
  the 
  species 
  are 
  naturally 
  

   large-headed, 
  these 
  giant 
  specimens 
  have 
  a 
  most 
  striking 
  

   and 
  even 
  formidable 
  appearance. 
  A. 
  bucephala, 
  spinigera, 
  

   trimmerana, 
  fulva, 
  synadelpha, 
  fucata, 
  denticulata 
  and 
  

   others 
  are 
  conspicuous 
  examples, 
  but 
  even 
  in 
  small 
  species 
  

   such 
  as 
  chrysosceles 
  and 
  minute 
  ones 
  like 
  minutula 
  one 
  

   meets 
  with 
  individuals 
  grossly 
  oversized 
  and 
  sufficiently 
  

   conspicuous 
  amongst 
  the 
  normal. 
  

  

  Most, 
  if 
  not 
  all, 
  species 
  of 
  Andrena 
  emit, 
  when 
  handled, 
  

   a 
  very 
  distinct 
  odour, 
  and 
  this 
  is 
  sometimes 
  the 
  case 
  with 
  

   both 
  sexes. 
  Kirby 
  in 
  his 
  wonderful 
  old 
  book 
  refers 
  to 
  

   this 
  under 
  several 
  species. 
  Thus 
  of 
  Melitta 
  pilipes, 
  he 
  

   says 
  : 
  " 
  Alliu?n 
  spiral 
  recens 
  insectum." 
  A. 
  gwynana 
  

   and 
  fulvicrus 
  are 
  also 
  said 
  to 
  smell 
  of 
  garlic. 
  But 
  parvula 
  

   '' 
  moscham 
  spiral" 
  and 
  afzeliella 
  " 
  suavetn 
  spargit 
  odorem." 
  

   To 
  myself 
  the 
  majority 
  of 
  species 
  are 
  mildly 
  unpleasant, 
  

   e. 
  g., 
  A. 
  albicans, 
  but 
  some, 
  if 
  not 
  actually 
  pleasant, 
  are 
  

   certainly 
  less 
  unpleasant 
  than 
  others. 
  A. 
  denticulata 
  

   emits 
  an 
  odour 
  unlike 
  that 
  of 
  such 
  other 
  Andrenas 
  as 
  I 
  

   have 
  examined 
  in 
  this 
  respect. 
  Mr. 
  A. 
  H. 
  Hamm 
  suggested 
  

  

  