﻿376 
  ANNUAL 
  REPORT 
  SMITHSONIAN 
  INSTITUTION, 
  1922. 
  

  

  piracy. 
  Frequently 
  the 
  robber-fly 
  would 
  come 
  and 
  crouch 
  motion- 
  

   less 
  near 
  the 
  nests, 
  alert 
  for 
  booty. 
  Whenever 
  an 
  unsuspecting 
  wasp 
  

   drew 
  near, 
  swiftly 
  the 
  Asilid 
  would 
  rise 
  and 
  strike 
  at 
  it 
  hawk-like 
  

   with 
  legs 
  extended 
  ; 
  but 
  most 
  often 
  the 
  intended 
  victim 
  escaped. 
  The 
  

   home-coming 
  Philanthi 
  laden 
  with 
  their 
  bees 
  fell 
  more 
  easily 
  into 
  

   the 
  pirate's 
  clutches. 
  One 
  case 
  in 
  particular 
  is 
  worth 
  recording. 
  As 
  

   the 
  wasp 
  burdened 
  with 
  its 
  bee 
  came 
  into 
  sight 
  the 
  robber-fly 
  pounced 
  

   upon 
  it 
  and 
  caught 
  both 
  the 
  wasp 
  and 
  her 
  prey 
  between 
  its 
  long 
  

   spiny 
  legs. 
  Then 
  with 
  its 
  two 
  captives 
  dangling 
  from 
  its 
  talons 
  the 
  

   Asilid 
  flew 
  off. 
  I 
  followed 
  to 
  see 
  the 
  finish. 
  The 
  tableaux 
  was 
  

   remarkable. 
  The 
  fly 
  hung 
  nonchalantly 
  by 
  one 
  leg 
  from 
  a 
  near-by 
  

   branch 
  and 
  with 
  its 
  sharp 
  beak 
  drained 
  the 
  juices 
  of 
  its 
  double 
  

   catch. 
  The 
  incident 
  was 
  not 
  without 
  dramatic 
  irony 
  — 
  the 
  assassin 
  

   being 
  despoiled 
  b}- 
  another 
  assassin. 
  To 
  complete 
  the 
  tragedy 
  I 
  cap- 
  

   tured 
  the 
  second 
  assassin. 
  When 
  its 
  Bertillon 
  prints 
  were 
  taken 
  

   the 
  robber-fly 
  was 
  found 
  to 
  be 
  Deromyia 
  discolor 
  Loew 
  (det. 
  Dr. 
  

   Aldrich). 
  

  

  I 
  wish 
  to 
  acknowledge 
  my 
  indebtedness 
  to 
  my 
  friend, 
  Rev. 
  John 
  A. 
  

   Brosnan, 
  S. 
  J., 
  of 
  Woodstock 
  College, 
  for 
  his 
  valuable 
  services 
  in 
  

   taking 
  the 
  photographs 
  for 
  this 
  paper. 
  To 
  Mr. 
  Sievert 
  A. 
  Rohwer, 
  

   of 
  the 
  United 
  States 
  National 
  Museum, 
  I 
  am 
  also 
  obliged 
  for 
  deter- 
  

   mining 
  nearly 
  all 
  the 
  species 
  of 
  Hymenoptera 
  involved 
  in 
  this 
  discus- 
  

   sion 
  and 
  verifying 
  my 
  determinations 
  of 
  the 
  rest. 
  For 
  this 
  and 
  other 
  

   assistance 
  which 
  Mr. 
  Rohwer 
  rendered 
  me 
  during 
  the 
  preparation 
  of 
  

   this 
  paper 
  I 
  am 
  happy 
  to 
  express 
  here 
  my 
  sincere 
  gratitude 
  and 
  

   appreciation. 
  

  

  