﻿228 
  Mr. 
  R. 
  C. 
  L. 
  Perkins 
  on 
  

  

  that 
  the 
  odour 
  resembled 
  that 
  of 
  burnt 
  sugar, 
  and 
  this 
  is 
  

   perhaps 
  as 
  near 
  a 
  comparison 
  as 
  can 
  be 
  made. 
  

  

  Some 
  of 
  the 
  bees 
  of 
  this 
  genus 
  feign 
  death 
  when 
  alarmed, 
  

   and 
  may 
  be 
  seen 
  lying 
  on 
  their 
  backs 
  on 
  the 
  ground 
  or 
  

   at 
  the 
  bottom 
  of 
  the 
  net 
  after 
  capture 
  with 
  their 
  limbs 
  

   closely 
  appressed 
  to 
  the 
  body. 
  This 
  condition 
  is 
  assumed 
  

   much 
  more 
  readily 
  by 
  some 
  species 
  than 
  others. 
  Some 
  

   of 
  the 
  small 
  species 
  of 
  the 
  minutula 
  group 
  when 
  the 
  net 
  

   is 
  placed 
  over 
  them 
  will 
  often 
  fall 
  at 
  once 
  to 
  the 
  ground, 
  

   and 
  remain 
  motionless 
  amongst 
  the 
  grass 
  roots 
  till 
  one's 
  

   patience 
  is 
  exhausted 
  in 
  waiting 
  for 
  them 
  to 
  fly 
  up. 
  Some 
  

   are 
  much 
  more 
  willing 
  to 
  feign 
  death 
  when 
  the 
  sun 
  dis- 
  

   appears 
  than 
  when 
  it 
  is 
  shining 
  hotly, 
  and 
  some 
  are 
  able, 
  

   like 
  insects 
  of 
  other 
  Orders, 
  to 
  slip 
  along 
  on 
  their 
  backs 
  

   without 
  the 
  use 
  of 
  their 
  legs, 
  which 
  remain 
  appressed 
  to 
  

   the 
  body. 
  Species 
  of 
  the 
  wilkella 
  group, 
  A. 
  chrysosceles, 
  

   A. 
  albicans 
  notably, 
  and 
  probably 
  many 
  others 
  feign 
  death, 
  

   and 
  will 
  remain 
  quiescent 
  for 
  a 
  considerable 
  time 
  at 
  the 
  roots 
  

   of 
  herbage, 
  no 
  doubt 
  until 
  they 
  consider 
  the 
  danger 
  is 
  past. 
  

  

  Andrena 
  has 
  numerous 
  natural 
  enemies, 
  the 
  bees 
  of 
  

   the 
  genus 
  Nomada 
  and 
  the 
  remarkable 
  Strepsipterous 
  

   Stylops 
  being 
  of 
  special 
  interest. 
  A 
  few 
  species 
  are 
  also 
  

   attacked 
  by 
  members 
  of 
  the 
  genus 
  Sphecodes 
  — 
  most 
  of 
  

   which 
  are, 
  however, 
  parasites 
  of 
  Halictus 
  — 
  and 
  by 
  the 
  

   conspicuous 
  and 
  beautiful 
  flies 
  of 
  the 
  genus 
  Botnbylius* 
  

   Some 
  of 
  the 
  Conopidae 
  also 
  appear 
  to 
  be 
  attached 
  to 
  

   Andrena, 
  and 
  they 
  may 
  be 
  noticed 
  flying 
  at 
  and 
  striking 
  

   against 
  the 
  bees 
  as 
  they 
  fly 
  around 
  hedges 
  or 
  bushes, 
  and 
  

   even 
  pursuing 
  them 
  for 
  some 
  distance. 
  We 
  have 
  seen 
  

   one 
  species 
  follow 
  a 
  laden 
  ^ 
  oi 
  A. 
  nitida 
  right 
  to 
  its 
  burrow 
  

   and 
  cling 
  to 
  it 
  there. 
  One 
  may 
  suppose 
  that 
  this 
  pro- 
  

   ceeding 
  is 
  for 
  the 
  purpose 
  of 
  oviposition, 
  so 
  that 
  the 
  larva 
  

   of 
  the 
  fly 
  may 
  be 
  carried 
  into 
  the 
  bees' 
  burrow, 
  but 
  I 
  have 
  

   no 
  information 
  as 
  to 
  the 
  actual 
  deposition 
  of 
  an 
  egg, 
  

  

  * 
  Chapman 
  observed 
  the 
  oviposition 
  of 
  Bombylius 
  major 
  at 
  the 
  

   burrows 
  of 
  Awlrena 
  lahialis, 
  and, 
  as 
  mentioned 
  hereafter, 
  I 
  have 
  

   seen 
  the 
  .«ame 
  fly 
  at 
  pure 
  colonies 
  of 
  .4. 
  flavipes, 
  but 
  it 
  is 
  not 
  at 
  

   all 
  confined 
  to 
  these 
  two 
  species. 
  On 
  April 
  3, 
  1911», 
  a 
  dense 
  colony 
  

   of 
  A. 
  c'arkella 
  was 
  found 
  with 
  one 
  or 
  two 
  empty 
  pupa 
  cases 
  of 
  

   Bomhylius 
  minor 
  in 
  the 
  opening 
  of 
  nearly 
  every 
  burrow, 
  and 
  some 
  

   of 
  the 
  flies, 
  recently 
  emerged, 
  were 
  sunning 
  themselves 
  on 
  the 
  

   bare 
  earth 
  in 
  which 
  the 
  colony 
  was 
  placed. 
  No 
  doubt 
  the 
  formid- 
  

   able 
  armature 
  of 
  curved 
  spines 
  on 
  the 
  head 
  of 
  the 
  pupa 
  beneath 
  

   serves 
  to 
  enable 
  it 
  to 
  reach 
  the 
  mouth 
  of 
  the 
  bees' 
  burrow, 
  before 
  the 
  

   fly 
  emerges. 
  

  

  